The bank, which analyses and trades in the shares of US financial services companies and advises US firms in the sector, believes there is potential for growth in Europe.
KBW announced it was opening a London branch in April and began trading there in late July.
A KBW spokesman said financial services companies made up 29 per cent of the FTSE Eurotop 300.
Edelman head of financial and investor relations Stephen Benzikie will lead the account, reporting to KBW director of European research Vasco Moreno.