The three are suspected of abuse of power and money laundering which illegally earned them €921,320 ($1.3 million), an interior ministry statement said.
An interior ministry spokesman told the HINA news agency that the three were arrested as part of a probe into the alleged bribery of local officials by Daimler.
According to local media reports, in 2003 the then government, headed by the Social Democrats, struck a deal with Daimler to buy 210 fire-fighting vehicles worth some 800 million kunas (€110 million euros).
Media said that the car maker gave Croatian officials some €4.7 million in bribes to ensure the deal.
Daimler has admitted making hundreds of improper payments worth tens of millions of dollars to foreign government officials in at least 22 countries, including Croatia, between 1998 and 2008.
Two of the men arrested Tuesday owned a local car parts firm which received €250,000 from an unnamed German-based company in an apparent loan that was never repaid, the interior ministry statement said.
The third man allegedly received €1.6 million on his US-based firm account for consultant services that were never provided, it said.
The fictitious services were presented as being given to a German-based company for moves to be made to reach a deal with the Croatian government to buy 210 fire-fighting vehicles in 2003, the statement said without elaborating.