The case of the German-registered cars, including 93 BMWs located via GPS,has caused friction between Germany and the Central Asian country, Bild newspaper reported.
A German foreign ministry spokeswoman did not confirm the Bild report that former foreign minister Guido Westerwelle had called in the Tajik ambassador over the case this year.
However, she told AFP that "there have been talks with the Tajik side on cooperation in fighting organized crime".
The cars were located by the "Westwind" task force of German and Lithuanian investigators, mostly using the vehicles' GPS systems, said Berlin city justice department spokeswoman Lisa Jani.
When Tajik authorities failed to respond to requests to help in the investigation, Berlin's justice minister Thomas Heilmann wrote to Germany's then-foreign minister Westerwelle, she told AFP.
"Most of the vehicles are in the possession of people who have business or family ties with the family of the Tajik president," Heilmann wrote to the foreign minister, said Jani.
Tajikistan has to date not replied to the request for legal assistance or taken steps to return the cars, she added.
An official contacted at the Tajik embassy in Berlin said he could not immediately provide an official statement.