MOSCOW, JUNE 9 -- A Soviet spokesman said today that it is "realistic to hope" for a U.S.-Soviet summit meeting this year, most probably in the late fall.

Boris Pyadishev, deputy Foreign Ministry spokesman, noted that a draft treaty on the elimination of medium-range missiles in Europe could be readied by September or October and that a "summit might take place any time after that deadline."

Pyadishev noted that before a summit, Soviet Foreign Minister Eduard Shevardnadze and Secretary of State George P. Shultz will meet in Washington, although he said no date has been set.

"Positive results" from a Shultz-Shevardnadze meeting "would make it possible to review the question of a Soviet-U.S. summit," he said.

The Soviets have stressed that a third meeting between President Reagan and Soviet leader Mikhail Gorbachev would be possible only if "concrete results" can be achieved. A summit is "no place for political tourism," Pyadishev said today.

He said the signing of an agreement on medium-range missiles, and the elaboration of "key provisions" on strategic weapons, antimissile defenses and a nuclear test ban, "might form the basis for a meeting at the highest level." The Soviets have used the same formulation in defining the terms of a summit since April.