The purpose of this paper is to report findings concerning the effects of cadmium , copper, and mercury on the brine shrimp Artemia Salina, of the Great Salt Lake. Metal toxicity was observed in relation to acute susceptibility, growth, reproduction, and hatching of the brine shrimp. Heavy metal concentrations such as cadmium, copper, and mercury are known to be considerably higher in the Great Salt Lake than those in both freshwater and seawater. No published study has been concerned with heavy metal effects on organisms in salinities greater than seawater (35 grams per liter total dissolved solids). The experiments reported in this paper were carried out in salinities approximating the Great Salt Lake (150-320 grams per liter total dissolved solids). Results of this study indicate that cadmium, copper, and mercury toxicities to the brine shrimp may not be comparable at varying salinities. Findings of acute toxicity experiments were compared to other heavy metal studies on marine organisms. The brine shrimp was found to be very resistant to cadmium and copper poisoning and moderately resistant to mercury. Neither cadmium nor copper inhibited hatching of the brine shrimp eggs although mercury caused severe inhibition at concentrations of 0.3 milligrams per liter. Only cadmium at concentrations between 1.0 and 33 milligrams per liter significantly suppressed growth rate and reproduction. Mercury and copper were not found to affect growth and reproduction below concentrations causing acute poisoning. Mercury was found to be the most lethal to the adult brine shrimp with a range of times to 50 percent mortality from 126 to 8.5 hours at mercury concentrations of 0.01 to 100 milligrams per liter respectively. Copper caused mortalities at concentrations of 1 to 67 milligrams per liter with respective times to 50 percent mortality of 124 and 12 hours. Copper was shown to precipitate out at concentrations near 12 milligrams per liter, Cadmium was found to be the least lethal with a range of times to 50 percent mortality from 94 to 320 hours with respective cadmium concentrations of 100 and 3.3 milligrams per liter.