In a busy round of late-summer summits, West German Chancellor Helmut Schmidt will meet here with Polish leader Edward Gierek Aug. 19 and 20, then travel to the East German Baltic port of Rostock for long-postponed talks with East German leader Erich Honecker Aug. 27 to 29.

The visits are another sign of West Germany's determination to maintain contact with the Soviet-dominated East European countries in the face of the Soviet occupation of Afghanistan. Coming less than two months before the West German national elections, the visits also are seen as a way for Schmidt to promote himself as a peace candidate, a major theme of his campaign.

Under pressure from the Christian Democrat opposition to secure concrete concessions from the meetings, Schmidt's government has sought to minimize expectations for broad results.

The problem for Schmidt will be to obtain visible gains from East Berlin and Warsaw without too great a cost to Bonn during this election year.

The polish chief will be looking for major new credits from Bonn totaling $860 million for his hard-pressed communist state. Joint exploration of Poland's coal reserves is the most obvious way in which West Germany can profitably assist the Warsaw leadership and the country's ailing economy.

But while Bonn is anxious to strengthen trade links, it can do only a limited amount to boost West Germany business confidence in investing in Poland, given the wariness about Poland's heavy debt, put at about $19 billion. Poland's financial crunch took a further blow last month when industrial unrest forced the leadership to concede 10 percent wage increases.

The more critical East-West German summit will be the first formal meeting between heads of government from the two German states in 10 years, although Schmidt and Honecker met informally after funeral of Yugoslav president Tito in Mays.

While Schmidt is expected to press for greater family visitation rights between East and West Germans, Honecker is likely to seek more aid to improve East German rail lines between Berlin and the West German border. He is also said to want to sell electricity from a power station built with Bonn's assistance.

Originally delayed because of the Soviet invasion of Afghanistan, the German summit was eventually cleared as result of Schmidt's visit to Moscow at the end of June. While relations between Washington and Moscow have been decidedly chilly, East and West Germany have made a point during the past six months of moving closer together, accelerating joint long-term projects and producing statements of an unusually friendly tone.