HANGZHOU, Sept. 10 (Xinhua) -- Chinese billionaire Jack Ma officially announced his retirement Tuesday as chairman of the Alibaba Group at a function to mark the company's 20th anniversary.

The co-founder of the e-commerce giant who turns 55 Tuesday will continue to serve on Alibaba's board of directors until the general meeting of shareholders in 2020 and remain his permanent membership of Alibaba's partners.

Ma handled over the CEO position in 2013 and made an announcement in an open letter on Sept. 10, 2018, saying that he would step down in a year, with the company CEO Daniel Zhang taking over as the new chairman.

"The value of life should be seen in what a man has experienced and not in what he has received," Ma said, noting that he is not "retiring" but to spend more time and energy on education, philanthropy and environmental protection.