KIEV, U.S.S.R., JULY 30 -- The Ukraine stepped up its defiance of Moscow today with a demand that all Ukrainians doing national service in the Soviet army be transferred to duty in their native republic.

The demand came in the form of a resolution by the republic's legislature calling on the Soviet Defense Ministry to withdraw all Ukrainian enlisted men from such ethnic trouble spots as Soviet Kirghizia, Azerbaijan and Armenia by Oct. 1 and that those serving in other Soviet republics should be returned to the Ukraine by Dec. 1.

"I see this as a first step toward formation of national armed forces, a Ukrainian army," said Ivan Drach, leader of the Ukrainian nationalist organization Rukh. "Our sons should not be involved in these ethnic conflicts."

The resolution, if acted upon, could have a significant impact on the Soviet Union's 4.5-million-member military, which includes a large proportion of Ukrainians. The measure was approved by a vote of 282 to 31 votes in the legislature, where Communist legislators hold a firm majority.

"Sovereignty is nothing but a piece of paper if the country does not have its own armed forces," Drach remarked of the overwhelming vote.

The Ukrainian legislature, following a number of other Soviet republics, issued a declaration of sovereignty earlier this month, proclaiming the supremacy of Ukrainian laws over Soviet legislation. One of the most prosperous of the 15 Soviet republics and the second most populous after Russia, it went further than most others in proclaiming its right to raise its own armed forces and introduce a separate currency.

Many legislators noted that the military recall will be extremely difficult to enforce, but that like similar moves by the rebellious Soviet Baltic republics, it has, at the least, symbolic importance as an expression of long-term self-determination.