Ronald Reagan said today that U.S. athletes and not the U.S. Government should make the decision on this nation's participation in the Summer Olympics.

"I would leave that decision to the athletes themselves," Reagan said at a news conference here. "I don't believe our government should be in the position of saying you can't have a visa, you can't leave the country or go . . .?

Reagan, who originally supported President Carter's call for a boycott of the Olympics, said last week he was changing his view. He said he had a "sympathetic feeling for the youngsters who worked their heads off" training for the Summer Games in Moscow.

This morning Reagan still appeared to have a somewhat unsettled view of the boycott. At one point he said he thought the boycott was worth another try. Later he said he thought it had failed.

"I still think the United States should make an effort. I guess the final decision hasn't been made by a number of countries, and maybe we can invite them to hold games here as a substitute for that."

A few moments later Reagan said that a boycott by only the United States would fail to impress the Soviet people that world public opinion was outraged by the Russian invasion of Afghanistan.

"If just one country doesn't show up, I think the Soviet propaganda machine probably grinds out something like the United States didn't come because they were afraid of getting beaten. . . ."

Reagan said he thought it would be impossible for individual athletes to go on their own, adding it would be necessary for the entire team to make this decision. If the athletes decide to go as a team, he said, they should be allowed to do so.

"There's something about our government telling our people they can't leave our shores that I can't buy," Reagan said.

The former California governor campaigned today in Kansas and Wisconsin on the eve of primaries in those states. He then flew off to Louisiana, which holds its primary on Saturday.

In both Kansas and Wisconsin, Reagan was asked about whether he had been politically damaged by a statement he made last week in which he appeared to show an ignorance about the meaning of parity prices for farmers. Reagan said he was trying to avoid committing himself to 100 percent parity and said he did not think that he had been damaged by his statements.