South Africa's feisty white advocate for human rights

She is a small, attractive white woman with a strong face, iron-gray hair, and penetrating blue eyes, who has never hesitated to tell her government exactly what she thinks of it.

And the government, nettled by her incessant questions in the magnificently pillared Parliament, complains she is embarrassing it.

''It's not the questions that are embarrassing,'' she shoots back, ''it's your answers.''

For 30 years, Helen Suzman has been relentlessly prodding South Africa's conscience - especially on the treatment of the country's 22 million voteless blacks.

Prime Minister P. W. Botha, the only member of Parliament who has served longer than she has, has said her nagging is like water dripping on a tin roof. But he has never succeeded in turning it off. Once he even tried threatening her after she took part in an illegal march protesting the expulsion of black squatters.

''You try to break the law, and you will see what happens to you,'' the stern prime minister warned her in Parliament.

Mrs. Suzman, who has never been deterred by threats, telephone tapping, and the opening of her mail, fired back: ''I am not frightened of you. I never have been and never will be. I think nothing of you.''

Despite three decades of political opposition (she was first elected in 1953) , Mrs. Suzman gives no sign that she has grown tired of the political fray. If anything she appears to relish it. The only difference, she says with a chuckle, ''is that I've become nastier.''

That kind of feistiness has won Mrs. Suzman both respect and ridicule in her country. From time to time her government critics have facetiously called her ''Mother Superior,'' but she has crossed swords with the government so long now that she wonders in a moment of self-deprecatory humor whether she couldn't be called ''Grandmother Superior.''

Overseas, her stands on apartheid have won her several international fellowships. She is also the recipient of seven honorary doctorates (Oxford, Harvard, Columbia, Smith, Brandeis, Denison, and Witwatersrand, her alma mater in Johannesburg).

Right now she is sitting at a breakfast table in a Cambridge, Mass., hotel overlooking the Charles River, recounting her struggles and noting some changes that have taken place within the last decade in her native land. She speaks of it with affection. And like her friend and political brother, Alan Paton, she says, ''It is a beautiful land.''

There are times when infuriated right-wing critics have told her to ''go back to Israel'' or ''go back to Moscow,'' but she has no intention of going anywhere unless it is a short trip abroad such as the one she is enjoying now to the United States.

She would have come earlier but she was busy fighting the government's Nov. 2 referendum to bring Coloreds (people of mixed race) and Indians into a limited share of government with the whites. She opposed the move, as she does most government measures, because the proposal - voted in by a 2-to-1 margin by the white electorate - permanently excludes blacks, who represent 72 percent of the population, from the political process.

Mrs. Suzman believes the government of P. W. Botha is adamant that the political home of the blacks has to be in special ''homelands,'' or rural reserves, set aside for them. ''It is the ethical justification for not giving blacks the vote. Nothing else will work because of their fear of being completely dominated and overwhelmed by a black majority.''

Now after years of endlessly haranguing the government, and recognizing by her own admission that the fundamental structure of apartheid remains largely intact, did she not feel beaten down? Weren't there times when she wanted to throw in the towel?

Her reply in that unmistakably flat South African accent that falls somewhere between the round vowels of the English and the more strident Australian equivalent could not have been more emphatic.

''No, I am not beaten down. I'm resilient. I always tell my children I came from good peasant stock,'' says this refined woman with a playful smile.

''Yes, I've had my moments of frustration when I've said why am I spending my life in this unrewarding occupation? '' she remarked without a tinge of long-suffering, ''but then something always crops up. It's my ire that gets me up.''

Righteous indignation is what seems to galvanize Mrs. Suzman. ''I'm not a sentimentalist. I don't go around with tears of pity.''

For her a principle is at stake. ''It's a question of simple justice. If blacks had equal opportunities, I wouldn't be in the business.'' And she would be the first to disclaim that she alone stands for human rights in South Africa. Or that in some way she is the great white hope for dispossessed Africans.

''I'm not their spokesman. I speak on issues. It just so happens that what I say coincides with what they say or like to hear.''

In practical terms it means, because of her privileged parliamentary position , that she can secure passports for Africans and intercede for political prisoners. She helps provide these political prisoners with access to legal representation and takes newspapers to many in jail.

But she also recognizes that there are blacks who want no part of her, who look to their own people to complete the struggle. She accepted that years ago. But it doesn't deflect her from doing what she feels is right.

She is not optimistic about the future. But then she is not all pessimistic about the recent past, either.

For 15 years she was the sole representative in Parliament of the Progressive Federal Party. Now she has company - 26 other Progressives who share her political philosophy. And that, she finds, ''is rather jolly.'' The Progressives , or Progs, as they are usually called, are now the official opposition, even though they are crushed by the huge National Party majority in Parliament. ''We now represent 20 percent of the white electorate,'' she says in a voice that suggests that's no mean accomplishment, given her earlier years of solitude in the legislative body.

But in the sharply polarized world of South African politics, Mrs. Suzman is rejected as much by African nationalists as she is by white nationalists.

Ahmed Gora Ebrahim, head of the observer mission to the United Nations of the outlawed Pan-Africanist Congress, faults Mrs. Suzman for trying to cushion rather than remove the government.

''She's acting as a buffer between the racists and those who want to overthrow the whole system.'' In his view Mrs. Suzman's party ''represents the most exploitative class in South Africa - the business community. She is not opposed, as far as I am concerned, to apartheid per se. She's only opposed to those aspects of apartheid that hinder big business, such as job reservation.''

Carl Frank Noffke, a former editor of Die Transvaler, the mouthpiece of the Nationalist Party in Transvaal Province, who remembers her speeches in Parliament back in the 1950s, calls her ''an outstanding woman.''

However, he thinks that for all her qualities, Mrs. Suzman would be unable to look back on her 30 years and draw up a ''long list of achievements.'' Mr. Noffke identifies Mrs. Suzman with the more liberal wing of a party that enjoys the support of only a minority of whites. These whites were divided, he said, on how they should vote for the constitutional proposals. As a result he foresees a split in the Progressive Party.

Mrs. Suzman brushed off such a notion, confident that despite these differences, party members would return to the political fold at election time.

Looking back over the past 10 years, she sees changes. Some of them, she suggests, are symbolic. Some are psychological.

A Rip van Winkle returning after 10 years might be surprised to see such tangible differences as the elimination of segregation in post offices, on some beaches and municipal parks, and many integrated hotels, restaurants and theaters. In most big cities ''whites only'' signs have gone from park benches and elevators. Banks, which were the preserve of whites except for menial help, now have blacks as tellers and sometimes even as managers.

Nowhere is the lowering of the color bar more conspicuous than on the sports field. Mrs. Suzman has no illusions that these changes are designed less to bring about integration than to appease international opinion.

But she adds that the international community is not impressed. South Africa has not been welcomed back to the Olympic Games. ''The cry is not just 'desegregate sport and we'll let you back.' The slogan now is 'no normal sport in an abnormal society.' ''

This is true, she says, ''because as soon as they leave the sporting fields they go back to their segregated Sowetos, Coronationvilles, and Lenaisias. The basic structure of apartheid still stands.'' Soweto, Coronationville, and Lenaisia are residential areas in Johannesburg exclusively set aside for blacks, Coloreds, and Indians, respectively. To her the most significant changes have taken place in the labor field, especially the registration of black trade unions and opportunities for collective bargaining.

Because of expanded opportunities for blacks, Mrs. Suzman is against Western companies pulling up their stakes in the country in the hope of pressuring the government to change. ''Once you leave,'' she says, ''you have lost influence. Nobody listens to you.''