"This is something that has been put off for too long," Vucic said. "Changes and modernization are the key words."
Serbia's new government was voted into office on Sunday with 198 for and 23 against.
Vucic's Serbian Progressive Party has won a majority, taking 158 seats in the 250-member assembly in March 16 elections. The new Cabinet also included ministers from smaller allied parties.
Liberal opposition leader Dragan Djilas criticized the prime minister, saying he had offered no new solutions. Djilas said that "one man will be making all the decisions, which is not good for Serbia."
Vucic, who is a former hard-line nationalist turned pro-EU reformer, has gained popularity by promising an uncompromising struggle against rampant corruption amid widespread poverty.
Vucic said the economic changes will include cuts in the public sector, budget revision and privatization of state-run companies, coupled with boosting the private sector. He predicted possible protests, but pledged to stick to reform.
The EU opened accession talks with Serbia this year, after Belgrade agreed to normalize ties with Kosovo.