Leighton Bascom will take over the voluntary position from outgoing branch president Katie Presland, effective immediately and following an annual general meeting last month.
A chartered fellow at the CISI Mr Bascom is an investment manager and branch principal at Raymond James, managing individual and institutional investment mandates and responsible for the overall running of the firm’s Tunbridge Wells branch.
The CISI offers two grades of chartered membership, a chartered member, chartered MCSI, and a chartered fellow, chartered FCSI.
Prior to joining Raymond James in 2003, US-born Mr Bascom was senior vice president of investments at Prudential-Bache Securities in London.
A CISI spokesperson said Mr Bascom’s American background offered a "unique perspective" to global investing in London which many UK and European investment managers "may not share".
Mr Bascom said: "I believe my family and my faith are the foundations for success and happiness.
"I look forward to building on the excellent legacy put in place by my predecessor Katie Presland with the aim of growing the membership and developing an exciting annual continuing professional development programme."
Jim Winter, head of UK business development at CISI, said: "We are delighted to welcome Leighton as our new south east branch president and we would like to thank Katie Presland for her leadership and support with building the branch.
"With over 1,000 members, our CISI south east branch covers areas including Kent, Tunbridge Wells, Sevenoaks and Maidstone and is an integral and lively part of the business and finance community of the region."