PRESIDENT Reagan's foreign policy address today comes at a moment when the results of a major Soviet review of East-West relations undertaken late last autumn are coming into sharper focus.
The Soviets have clearly decided to hold to their hard-line insistence that Pershing II and cruise missiles come out of Europe before negotiations on either European- based or strategic nuclear weapons can be resumed.
They appear to have dismissed as mere election-year politicking the more conciliatory tone of Mr. Reagan's pronouncements ushered in by his Jan. 16 remarks.
Moscow, too, appears to be emerging from a period of foreign-policy doldrums which began during the final days of Leonid Brezhnev's rule and spanned the entire 16 months of Yuri Andropov's leadership. Recent signs of a new Soviet activism include visits by Deputy Premier Geidar Aliev to Syria and Defense Minister Dmitri Ustinov to India - both visits certain to result in major new Soviet arms transfers to the host nations. Additionally, there is the Caribbean voyage of the aircraft carrier Leningrad, an unprecedented event interpreted here as a signal that the Soviets intend to vie more actively with the US for political influence in the region.
The principal force behind these moves is undoubtedly Foreign Minister Andrei Gromyko. After 27 years in his current job and 11 on the Politburo, he is at the apex of his personal power and probably has greater influence over the conduct of foreign affairs than any Soviet foreign minister has ever enjoyed. Mr. Gromyko is regarded by Western diplomats as rigid in his insistence that strategic arms agreements follow the pattern set by SALT II and earlier accords and very negative in his view of the Reagan administration and its top officials.
If Gromyko and his colleagues are now acting more confidently in the foreign arena, recent Soviet commentaries suggest it is because they have concluded that President Reagan's anti-communist ''crusade'' is running out of steam. And they consider that for all his own activism, Mr. Reagan is subject to the same sorts of constraints in his international dealings as have encumbered every American president since the Vietnam era.
To Soviet eyes, a single event of Mr. Reagan's presidency was his decision to withdraw American marines from Lebanon, after having failed initially to grasp the correlation between policy objectives and the military and political resources necessary to achieve them.
Soviet commentators who only six months previously had been somberly bemoaning the ''complexity'' of the international situation, suddenly sprang gleefully to the attack. Typical were the words of Tass political analyst Anatoly Krasikov, who began one recent commentary as follows: ''The dismal failure of the military and diplomatic initiatives of the US administration in the Middle East has added another touch to the overall picture of the collapse of the foreign policy pursued by Washington today.''
As the Krasikov commentary suggests, the Middle East is not the only area where Reagan initiatives appear less threatening to the Soviets than some months back.
True, NATO missiles are now on the ground in Europe - a major Soviet setback, given the Soviets' enormous propaganda investment in blocking deployment - and such other White House programs as the MX and Midgetman are still on track. But the failure to achieve nuclear arms control accords now ranks as one of Mr. Reagan's biggest election year liabilities. And if the domestic political situation is manageable for the time being, the Soviets - whose foreign-policy strategy rarely turns on the outcome of a single round of Western elections - seem willing to wait while America's Democrats, West Germany's Social Democrats, and Britain's Laborites pose serious challenges to what until recently was impregnable strategic doctrine.
The Soviets continue to face frustrations in their re- lationship with China, given Mr. Reagan's grudging adherence to the main recent directions of American policy there. They have suffered political setbacks in southern Africa and have not been able to cajole or coerce Japan out of assuming a greater role in its own defense.
Yet the Soviets have, in the main, emerged from more than three years of the Reagan presidency remarkably less the worse for wear. Nettlesome sanctions imposed for their ongoing military campaign in Afghanistan were lifted early. The fire of nationalist passion and political reform in Poland has been controlled if not quenched. Lost political ground in Europe and the Middle East has been recaptured. Central America remains a resource - an attention-diverting problem in the US backyard.
Despite Mr. Reagan's perceived problems and the rich propaganda lode he has provided for them, the Soviets fervently wish to see him defeated in November.
The President's mammoth defense outlays continue to present unwanted security problems to Soviet leaders while undoubtedly forcing them to spend billions of rubles more on their own programs than might otherwise be the case. Mr. Reagan is considered by the Russians a risky fellow to have presiding over America's nuclear arsenal while his positions on nuclear arms control make impossible the sort of accords achieved with every US administration during the past 20 years. Such accords have been a central element in Soviet foreign policy during that period.
Moreover, the President's confrontational polemics, despite some recent moderation, run counter to the sort of dialogue Soviet leaders would prefer to conduct with their American counterparts.
If all recent indications are correct, the Soviets fear Mr. Reagan somewhat less than they did a short while back. But they do not like him any more. That is a formula for stalemate and rather high tension in the months immediately ahead.