Morse will take over the reins from former senior partner Richard Oldworth, who is moving to the new role of executive chairman.
In his new role Oldworth with spend more time servicing his existing clients, the most significant of which is the agency's owner WPP, and look to create new business opportunities by leveraging off WPP's international network.
Morse, currently a partner at the agency, joined Buchanan in 2000 from Merlin and has an investment banking background.
Morse said: ‘We want to work with UK and international companies that are ambitious at heart and want to grow their business through the equity markets.'
Buchanan is one of the leading financial PR firms for AIM clients, coming second to only FD in Hemscott rankings in both total AIM clients and AIM 100 clients.
Morse said the agency would look to further expand its roster of AIM clients, but it would be selective in working with companies with potential to move onto the main market.
He said: ‘Buchanan has often been associated with the smaller end of the market and we want to change that perception by bringing in bigger and better business.'
Commenting on Morse's appointment, Oldworth said: ‘Bobby has made a very valuable contribution to Buchanan's development over the last decade and has been instrumental in establishing our position in the mining and oil and gas sectors. My partners and I welcome Bobby to his new role and look forward to supporting him wholeheartedly in Buchanan's ongoing pursuit of providing excellent advice to quality growth companies.'