The prosecutors in Stuttgart suspect that bribes totaling about 100,000 euros ($125,000) were paid in connection with vehicle sales to the two countries, spokesman Tomke Beddies said.
Beddies said former DaimlerChrysler employees were among the suspects, but didn't say how many were involved or identify them further.
Investigators are examining suspected payments in 2003 to a recipient in Ghana who may be a government official and in the summer of 2004 to an employee of an unidentified Polish company.
Prosecutors are also examining DaimlerChrysler business related to Belgium, Beddies said. He didn't elaborate.
DaimlerChrysler AG said in March that an internal investigation of bribery claims found evidence of 'improper payments' in Africa, Asia and Eastern Europe and that several employees had been dismissed or suspended.
The company disclosed the findings in a filing with the U.S. Securities and Exchange Commission.
The SEC and the Department of Justice are investigating the company over whether it violated U.S. anti-bribery laws.