In the present study, the utilization and biosynthesis of sterols in Artemia salina were investigated. The results obtained are as follows:
1) In spite of being supplied with the two types of diets containing ergosterol, stig-masterol, β-sitosterol, campesterol, and unknown sterol, Artemia was found to contain only cholesterol as a sterol. The result suggested that Artemia may modify these sterols to chole-sterol.
2) It was shown by the tracer experiment that Artemia did not incorporate acetate into sterols. The result indicated that Artemia may lack sterol-synthesizing ability.