Authorities in Germany say around 4,500 migrants have crossed from Poland without documentation since August.
Germany has proposed introducing joint border patrols with Poland to help combat a rise in illegal migration from Belarus.
German Interior Minister Horst Seehofer has suggested that a "significant" increase in support on the Polish side of the border could identify illegal crossings and arrest people smugglers.
Seehofer announced on Wednesday that he had sent the proposals to his Polish counterpart Mariusz Kaminski.
But the interior minister added that no one had any intention of closing the frontier between Germany and Poland.
The European Union has blamed the rise in migration on the Belarusian regime of President Alexander Lukashenko.
The EU has accused the authoritarian leader of deliberately facilitating illegal migration into the bloc in revenge against sanctions on Minsk.
Authorities in Germany say about 4,500 migrants -- many from Syria and Iraq -- have arrived via Poland and Belarus since August.
Berlin says it has offered assistance to Poland by seconding additional border guards and providing logistical support for housing migrants in the country.
But Seehofer stopped short of introducing regular checks on the border.
"Poland for their part have taken very, very strong initiatives to prevent irregular immigration," Seehofer told reporters after a Cabinet meeting.
German officials have also raised concerns about the humanitarian situation of migrants picked up at the Poland-Belarus border.
Poland has deployed 6,000 troops along the border with Belarus to try to stop the influx of migrants, Defence Minister Mariusz Blaszczak said on Tuesday.
"The soldiers support the border guards by protecting the country's border and preventing it from being crossed illegally," Blaszczak said on Twitter.