This report reviews current literature regarding the association of the pharmaceutical preservative thimerosal and other mercury exposures with the risk for autism. The evidence presented here does not support a causal association between autism and mercury exposure from the preservative thimerosal. The risk for autism from other mercury exposures such as from dental amalgam restorations or environmental mercury release into the atmosphere is ambiguous. Since mercury is a known neurotoxin, more research should be done to ensure that mercury exposure from any source does not contribute to autism.