"I am resigning so as to enable the government to work in peace in these troubled times," Petrovič told reporters. He denied any wrong-doing.
Petrovič used to work for publisher DZS which is accused of acting in a cartel with others when selling stationery to the government from 2007 to 2012, according to Slovenian media. The company has so far made no comment on the accusation.
Petrovič is the first minister to resign from the centre-left government of Prime Minister Miro Cerar which was appointed a month ago after a snap election in July.
"This resignation will not hurt the stability of the government but it is hard to imagine that the government will be able to last its full four-year term with all the challenges it is facing," said Meta Roglič, a political analyst at daily Dnevnik.
Slovenia narrowly avoided an international bailout for its banks in December and has to reduce its budget deficit to below 3 percent of GDP next year from 4.4 percent seen in 2014. Roglič said the main challenge facing the government was to pass the 2015 budget plan.
Petrovič is a member of Cerar's SMC party which is in a coalition with the pensioners' party Desus and the Social Democrats.
Zaradi testiranja je dodanih umetnih 2 sekunde delaya.