Accepted: March 25, 2012) Abstract: Removal of hydrogen sulfide from mixed gas was successfully carried out in a batch reactor. The isolated microorganism from Ramsar hot spring was cultured and adapted in an environment with hydrogen sulfide. At 35 C, maximum cell dry weight was 0.43 g/l. For the hydrogen sulfide removal, effect of temperature in the range of 25 to 45 C was investigated. The experimental results showed that the removal efficiency significantly increased with an increase in temperature from 25 to 35 C, then; a slightly decrease in media temperature at 45 C appeared. Maximum and minimum removal efficiencies of hydrogen sulfide were 72 and