Washington — Economic indicators are up in America and down in Russia. For the 10th straight month, the US Commerce Department's index of leading economic indicators shows the United States economy advancing. Preliminary figures show a vigorous 1.1 percent increase in April. Furthermore the Commerce Department revised the March index, raising it from 1.5 percent to 2.2 percent - a major improvement.
Meanwhile, the Congressional Joint Economic Committee (JEC) Tuesday issued its triennial study of the Soviet Union's economy. The study, compiled for the committee by the US Central Intelligence Agency, found the Soviet economy ''enmeshed in inefficiency'' because of overcentralization. The average annual rate of Soviet economic growth, it figured, has declined from 3.7 percent for the period 1971-78 to 1.3 percent in 1979-81. Left unanswered is whether the new Soviet leader, Yuri V. Andropov, will raise economic performance over his predecessor, Leonid I. Brezhnev.
Commenting on the US figures, released at the end of the seven-nation Williamsburg summit, White House spokesman Larry Speakes said the report ''is excellent news, and shows the recovery is solidly on course.''
Washington is waiting to see if the current business improvement is shallow or is here to stay. The new figures are based on the government's 11 sensitive leading economic indicators, which are designed to help forecast future economic activity. Nine of the 11 indicators advanced.
Issuing the report, Robert Orther, the Commerce Department's chief economist, said, ''It looks like we're going to beat the official growth projection of 4.7 percent (expansion of gross national product) during the four quarters of 1983 .''
He said he was not concerned that the indicators increased less in April than in March: ''The recovery is under way; there will be no relapse,'' he said, adding that any quicker pace would bring back inflation.
The improvements in the latest economic figures include these: The workweek of the average worker has lengthened; the average of 500 common-stock prices has risen; there are modest increases for factory equipment orders; new building permits are up. Looking at complicated tables, the experts rub their hands. The barometer seems up, they say.
The new US statistics contrast sharply with the approximately 1,000 pages compiled by Martin J. Kohn and others in a new study by the CIA's Office of Soviet Analysis. Mr. Kohn finds the Soviets ''in the doldrums'' in the 1980s, ''enmeshed in inefficiency, but avoiding collapse.'' One problem is ''poor performance in the farm sector'' due to bad harvests, the report says. But troubles go deeper: ''The slowdown was pervasive. Growth in industrial production has steadily declined,'' the analysis says, ''reaching a post-World War II low of 2 percent in 1981.''
Soviet leaders are telling citizens their troubles, Kohn reports, and the accounts are virtually identical to Western analyses. The growth of the Soviet Union's labor force has slowed, and the country is exhausting its most easily accessible energy resources. The study notes discouragement by consumers who can't buy goods.
Mr. Kohn finds many communists still convinced that ''tinkering can make the system work.'' Living standards are low. In the late 1970s they were one-third that of the US standards, and less than half the French and West German. Life expectancy of Soviet males is estimated at 61.9 years, down from 66. About half of those hospitalized in the Soviet Union have ailments associated with alcoholism, according to one survey.
The picture of the American economy, meanwhile, brought optimistic comments. The National Association of Manufacturers advanced its estimate of the year's prospective improvement. As President Reagan ended the Williamsburg summit he gave a hopeful picture of US recovery. However, unemployment is still 10 percent , with 11.9 million people idle.