The evolution rates of sulfur-containing gases were measured during temperature-programmed pyrolysis of coals in an atmospheric pressure, vertical micro-fixed-bed reactor. The results indicated the following, compared with the products evolved in N-2: carbon monoxide (CO) promotes the formation of carbonyl sulfide (COS); carbon dioxide (CO2) inhibits the evolution of sulfur-containing gases at temperatures below 600 degrees C and exhibits effects similar to those of CO above this temperature; methane (CH4) also inhibits the evolution of sulfur-containing gases at temperatures below 600 C but promotes the formation of H2S at temperatures above 800 degrees C; and hydrogen gas (H-2) improves the formation of hydrogen sulfide (H2S) and inhibits the formation of other sulfur-containing gases.