He started his diplomatic career in Ministry of Iran from 1980s. First, Taheri was Consul General in Istanbul and after 5 years he returned home and became the Director of Ministry of Foreign Affairs (M.F.A. ), then he upgraded to Director of Political Office and in 1989 he became Ambassador in New Zealand and after 4 years he returned home and became director of Political Office in M.F.A.
Taheri's career path involved a series of diplomatic roles within the Ministry of Iran, starting with Consul General in Istanbul and progressing through various positions including Director of the Ministry of Foreign Affairs (M.F.A.), Director of Political Office, and Ambassador to New Zealand.