The invention relates to a steam stripping method of process condensate in CO conversion. The invention is characterized in that the process condensate firstly enters the upper part of a carbon dioxide steam stripping tower for flashing evaporation; secondary steam from the upper part of an ammonia-evaporated steam stripper tower enters the bottom part of the carbon dioxide steam stripping tower and steam strips carbon dioxide by countercurrent contacting with the process condensate after flashing evaporation; the process condensate after flash evaporation and the steam stripped carbon dioxide carry out countercurrent contact; the process condensate after flash evaporation and steam stripping enters the upper part of the ammonia-evaporated steam stripper tower from the bottom part of the carbon dioxide steam stripping tower and is steam-stripped by low-pressure steam entering from a kettle of the ammonia-evaporated steam stripper tower; gas phase is treated by secondary condensation to obtain non-acid-coagulated gas and condensate sewage; and steam stripping water is obtained from the bottom part of the ammonia-evaporated steam stripper tower. The invention carries out steam stripping on the upper and lower towers to carbon dioxide and ammonia in the process condensate respectively, thus avoiding the possibility of coexistence of carbon dioxide and ammonia in a condensing system, effectively solving the problem that the steam stripping system of the process condensate in the conversion procedure occurs ammonium salt crystallization blockage and prolonging the period of stable operation of a conversion device.