He replaces Carmen Goicoa who will retire shortly, a bank spokeswoman confirmed.
Kowalski will lead a 4-strong comms team for the bank, reporting to President Jose Maria Arias Mosquera.
Prior to leaving Burson, Kowalski led Burson's marketing and corporate department in Madrid for over two years, drafting comms plans for the agency's Spanish clients. A Burson spokeswoman said 'he got a better offer to work for Pastor in La Coruna, which happens to be his hometown.'
Burson is currently looking for a replacement, she added. Kowalski and Goicoa could not be reached for comment.
His appointment comes shortly after Banco Pastor posted record earnings for 2005.
The bank said net attributable profits rose 111.4% to EUR124.6m and that its return on equity (ROE) improved by 5.2 porcentual points to 13.4%.
Because of the bank's strong performance (beating analysts' expectations for two consecutive years), market watchers have signalled the bank could become an acquisition candidate in the medium or long term.
Despite swashbuckling global expansions by bigger peers (notably Banco Santander Central Hispano (SCH), which acquired the UK's Abbey last year), Banco Pastor has kept a low international profile, sticking to its home market, where it Operates 540 branches.