President Reagan goes to Latin America with matched luggage - in the sense that he carries some of the same policies as the postwar President most conspicuously concerned with the region: John F. Kennedy. Reagan seeks joint hemispheric action against the export of weapons and agents from communist Cuba; so did Kennedy. Rea-gan seeks joint action to bolster flagging economies as in his Caribbean Basin initiative; so did Kennedy in his more encompassing Alliance for Progress.
The depth of the challenge may be suggested by the urgency of the same problems two decades later.
The question is whether Mr. Reagan will come back from his journey with another piece of matched luggage. This is the recognition that became clearer to Kennedy by his last year in office: Communist subversion had to be halted for the alliance to succeed, he said in 1963. But the ''big dangers'' to Latin America were ''unrelated to Cuba.'' They included ''illiteracy, bad housing, maldistribution of wealth, balance of payments diffi-culties.''
A similar perspective is virtually certain to be pressed on Mr. Reagan as he travels to Brazil, Colombia, Costa Rica, and Honduras. It is important that he send the right signals himself:
* One right signal is the trip itself.
It is good hemispheric politics. Even if only a gesture, it shows that Mr. Reagan sees that a gesture is worth making. He wants to mend fences with a Latin America largely alienated by the US tilt toward Britain in the Falklands crisis. He can argue that the US had to side with self-determination and against aggression while not prejudging the matter of sovereignty.
The trip is also good domestic politics. It speaks to the US's increasing Hispanic population. It speaks to the population as a whole, with its need to understand and appreciate its fastest-growing minority - and with its concern for fostering the conditions in Latin American countries to reduce the incentives for illegal immigration.
* Concentrating on Brazil makes sense during this first sortie. The timing is right, just after an enthusiastic display of the democratic impulse during the country's first elections in seven years. Brazil is a notable alumnus of the Alliance for Progress - during which, for all the skeptics, many nations did exceed economic goals. Its economic links with the US are many, as are the opportunities for growing cooperation as repressive governmental measures continue to be alle-viated.
* A nod to Costa Rica is appropriate. This tiny, tenacious democracy is a proof that developing countries do not have to have a measure of authoritarianism to survive.
* More dubious signals are threatened by Mr. Reagan's scheduled visit to Honduras and with the head of Guatemala, General Rios Montt, who came to power through a coup this year. Dialogue with both these nations is in order. But Mr. Reagan needs to make clear that visiting Honduras is not a calculated overt addition to the US's reported - and not denied - covert harassment of the neighboring Nicaraguan regime. Feelers for talks between the US and Nicaragua ought to be aided, not undercut, by President Reagan.
The meeting with General Rios Montt might well have been omitted in view of the difficulty in keeping it from seeming to condone the violence under his regime. Perhaps Mr. Reagan can turn the occasion toward a reaffirmation of US concern for human rights.
Rios Montt is credited for cutting back urban violence. But in the ostensible campaign against leftist guerrillas, Guatemalan forces have massacred more than 2,600 Indians and peasants since he came to power, according to Amnesty International.
Certainly there should be no furtherance of the administration efforts to resume some form of military aid to Guatemala. As Robert Garcia, chairman of the Hispanic congressional caucus, has suggested, the US dialogue with Rios Montt should be accompanied by contacts with the Guatemalan left to get a more complete picture of the situation. Some distance should be preserved by the US until the human rights record is improved.
It is by cooperation toward both economic and human rights progress that the US can help to check the communist subversion that waits to exploit any lapse.