The Reagan administration has gambled that high unemployment will not be a killing political issue next year as long as the economy is still recovering, and so far its gamble appears to be paying off.

The Labor Department announced yesterday that unemployment fell half a percentage point last month to 9.5 percent of the labor force. But even when it was at its peak of 10.8 percent last winter the administration was resisting anti-recession programs put forth by Democrats in Congress.

That resistance continues. The White House fought passage of a health insurance bill for the unemployed in the House this week, on grounds that it would add to the federal budget deficit. It fought farm and mortgage bailout bills and a new public works program earlier on the same basis.

Administration officials note that uneasiness over unemployment is coming down in the public opinion polls. And they point out that Prime Minister Margaret Thatcher's conservative government won reelection in Britain earlier this year in the face of a record 12.8 percent unemployment rate.

"It's not a problem," a senior White House official said of unemployment, now that it is moving down. "We're not talking about it, we're not meeting on it . . . . We're not about to back any efforts to push a jobs bill."

That attitude derives partly from political calculations, partly from economic. A basic rule of presidential politics is that any administration should inflict whatever pain it must early in its tenure and hold the pleasure until the next election nears.

Conservative strategists have also argued for years that inflation is a more important issue than unemployment, in that inflation affects everyone, unemployment just some fraction of the labor force.

For both these reasons, according to Reagan's political advisers, it made sense for Reagan to squeeze the inflation out of the economy early, even at the cost of recession, then have the economy recovering and unemployment drifting down with a low inflation rate toward the end of his term.

In addition they have argued on economic grounds that anti-recession programs tend to come too late to do much more than add to the deficit, and thereby retard rather than enhance recovery.

Thus, former White House domestic policy planner Edwin L. Harper said in an interview before he left the White House last week, "There's not much we want to do to make the jobs come faster because in our economic situation it would be a negative to pass a jobs bill that would enlarge the deficit. This is a time to wait, avoid doing damage to the recovery."

Democrats have responded predictably to the administration's hands-off attitude toward unemployment, calling the president "indifferent" to the unemployed.

"There's not much you can say about them but that they don't care about unemployed people," said Rep. Augustus F. Hawkins (D-Calif.), chairman of the subcommittee on employment opportunities of the House Education and Labor Committee. He has sponsored a $5 billion jobs bill, which has been stalled by opposition from the White House.

"The human suffering of being unemployed goes on, and they are talking about unemployment as just what they call a lagging indicator," Hawkins said. "This country shouldn't watch the White House cheering 10 percent or even 9 percent unemployment, but that is what is happening. This would start a revolution in any other country."

Reagan has argued that there is less pain in the record high unemployment rates of recent months than might at first appear.

"There is reason for encouragement," Reagan told reporters two weeks ago. "There's only a very limited number of people who have been unemployed six months or longer. And they are the hard core and they are the real basic problem we want to get to. But we have to deal with it as it is. And I think there is certainly very definite reason for hope of employment."

Officials of organized labor and Democrats, on the other hand, say there may be even more pain in unemployment than the overall rate suggests, that for some occupations and some areas it is much higher than the national average and looks as if it will be much slower to recede.

They point out that the largest declines in unemployment have been among white males, particuarly white-collar workers, and that unemployment for women, teen-agers and blacks remains high.

"Unemployment is not going down for some people," Rudy Oswald, chief economist for the AFL-CIO said recently. "There is considerably more improvement among whites than among blacks. White unemployment dropped by 1.1 percent since December, while black unemployment is up 1.8 percent.

"Unemployment among white-collar workers is about 3.5 percent," Oswald said. "That is a hell of a lot different than 10 percent among blue collar workers. They're laid off for longer and longer periods now."

According to data from The Washington Post/ABC News polls, the voters' rating of Reagan's handling of the economy has gone from a low of 38 percent approval-58 percent disapproval in January to 47 percent approval-50 percent disapproval in June. Similarly, while only 18 percent of respondents thought the economy was getting better in January, 36 percent said it was getting better by June.

Overall, according to the poll, unemployment is not the concern now that it was earlier in Reagan's term. Last October, 42 percent of likely voters cited it as the most important problem facing the country. But by this June, 31 percent of voters did so. However, unemployment remains the No. 1 worry of the people polled.

"I would tend to concur with Reagan's advisers that the issue is not an active negative against anybody right now," said Horace Busby, a former aide to President Johnson and a political consultant to several major businesses.

"No Republican defeats last November have been attributed to unemployment," he said. "In part, it's pretty clear the unemployed do not vote. Look at Rep. Robert H. Michel (R-Ill.). He had a big Caterpillar plant down in his district and he won easily. People seem to blame liberal, free-spending programs of the past as much as they blame big business or Reagan."