The accountancy firm, the largest independent in Scotland, completed 31 transactions in the 12 months between April 2013 and the end of March this year.
Although it had completed 40 deals in the previous 12 months they were generally of lower value.
Among the agreements Johnston Carmichael worked on in the most recent year were due diligence for the Business Growth Fund on its investment in Arran Aromatics.
It also worked on the sale of oil and gas business Sureclean to US-based National Response Corporation and acted for R&M Engineering ahead of taking funding from Maven Capital Partners.
Andrew Ewing, head of corporate finance at Johnston Carmichael, said: "These are significant figures which show an uplift in deal activity and a rise in the value of transactions.
"While we began to see an increase in activity in the previous year, the market has really picked up in the last 12 months."
Mr Ewing suggested that trend is likely to continue in the coming months.
He said: "It's also clear from the discussions we are having with clients that there is a growing appetite among companies looking to expand and diversify through acquisitions."
Separately, the firm has promoted Donald McNaught to partner. He had been director in charge of insolvency in Glasgow since 2011.
Led by chief executive Sandy Manson, Johnston Carmichael, posted a 7% increase in profits in the year to 31 May 2013.
The firm made £10.57m profit before partners' remuneration in the year, up from £9.87m in the previous period.
Announcing the results, in December, Mr Manson said the company had noticed a marked increase in confidence from the start of 2013.
Mr Manson said growth in the year to May last year was partly driven by the firm's merger with Aberdeen-based Ritson Smith.
He said it was in the market for more such deals.
Dealmakers at the big four accountancy firms in Scotland reported a surge in activity towards the end of last year.
They said Scottish firms in sectors like oil and gas, food and drink and life sciences could attract bid interest.
Among private equity investors, the Pirrie brothers' Nevis Capital business and Penta Capital said they were keen to do deals.