He will leave after serving out his three-month notice in order to assist in finalizing the audited accounts for the year to end March.
Joyner will be replaced by John Li as interim finance chief until a replacement is appointed.
Li is the CFO (China) of Beijing Chyau Fwu Properties Co Ltd, which is owned by the family of Primeline's chairman, president and largest shareholder - Victor Hwang.
Li has over 30 years' experience working in various financial capacities for public and private companies.
Li has previously served as interim finance chief from May, 2013, until the appointment of Joyner as chief financial officer in November, 2014.
Dr Ming Wang, chief executive at Primeline, said: "The board would like to thank Stuart for his contribution to the company over the past three years and we wish him well in his future endeavours."