Irene Chang, current general manager of the agency, will be promoted to the MD role effective 1 May.
Hsieh (pictured) told Campaign Asia-Pacific that he does not have a next move, and that at 55, he is planning on taking retirement.
He spent six years and eight months in the CEO role.
Hsieh has 29 years of experience in the media industry in Taiwan and China, including MD for Mindshare Beijing; executive director and chief negotiator for Carat Taiwan; and MD for Initiative Media Taipei.
Asked about his accomplishments, Hsieh cited recovery after the recession, with growth of 40 per cent in 2010 and 20 per cent in 2011, as well as continuous new business wins, low turnover, and the development of the agency's digital capabilities.