Barnett will join the company's executive committee, following the launch of Friends Life earlier in the year, when Friends Provident merged with Axa.
Barnett joins Friends Life from RBS, where he was HRD for RBS Insurance and latterly, HR chief operating officer for RBS Group. Barnett was heavily involved in the creation of RBS Insurance through the integration of the Direct Line and Churchill businesses.
Barnett will report to Friends Life CEO, Andy Briggs. Barnett said: "I am looking forward to helping build an organisation that will position Friends Life as an industry-leading life company."