The Robinson R44 light helicopter went down near the village of Sady, some 35km north-west of the Polish capital, at around 2pm.
A police river patrol fished an injured man and a woman from the water and brought them ashore.
They were then taken to hospital by an air ambulance, state news agency PAP reported.
Firefighters were tasked with stopping fuel leaking from the wreckage of the helicopter.
(pk)
Source: PAP