Keith Brown announced a second round of cash for the Bus Investment Fund, which last year provided 13 projects with grants totalling £4.2 million.
Transport Scotland is inviting organisations to bid for a share of the cash, with projects able to apply for up to £500,000 over two years.
The fund is open to public transport authorities that are working in partnership with bus operators, community transport groups, the NHS or others in the public or private sector.
Mr Brown said: “We set up the Bus Investment Fund in April last year to encourage and support partnership working to improve bus services for communities across Scotland, for example by improving infrastructure or raising quality.
“We were pleasantly surprised to receive 45 bids for a wide range of projects and were also encouraged to see the ambition, diversity and geographical spread of ideas.
“Following the interest shown in the first round of the fund and the range of proposals, I am pleased to announce further funding in a bid to increase the standard of bus services and patronage across Scotland.”