A simple, rapid method for the estimation of reduced inorganic sulfur in reduced environments such as lake sediments was developed. The method involves distillation in the presence of granular zinc and hydrochloric acid and determination of sulfide as the methylene blue complex. The method gives quantitative recovery of elemental sulfur, sulfide and thiosulfate, and partial recovery of other reduced forms of inorganic sulfur. Sulfate, persulfate and organic forms of sulfur are not determined by the method developed. The method is sensitive and highly precise, and has been found to be very useful in evaluating the sulfur status of lake sediments.