The two presidents talked about the efforts Croatia is investing to join the European Union, developments in Southeast Europe and other world affairs, the Austrian news agency APA quoted spokeswoman Astrid Salmhofer as saying.
She declined to go into further detail given that it was a private visit.
APA quoted her as saying that "it's easier to exchange views in a private setting". She did not rule out the possibility that Mesic and Fischer also talked about Ante Gotovina, the runaway Croatian general wanted by the Hague war crimes tribunal.
Mesic is the first foreign guest Fischer has received in the Muerzsteg summer residence since coming into office last year.
The Croatian president arrived in Austria yesterday.
Fischer invited Mesic for a visit because a trip to India prevented him from attending the Croatian president's February 18 inauguration.