This study investigated concentration of metal ions, intersexuality and histological alterations of digestive gland in Mytilus galloprovincialis. Samples were collected from two areas of Gamak Bay in May, 2010. The concentration of metal ions showed that Al (366.5 ± 249.7 mg/kg) was highest and Zn (179.5 ± 67.8 mg/kg) was second high concentration. Co (1.0 ± 0.2 mg/kg) was lowest. The intersexuality was 26.4% and males (38.8%) was higher than the females (12.9%). Intersex type was observed four types. Destruction of digestive tubule epithelium was highest among other biomarker in digestive gland. Distribution of basophilic cell and lipofuscin was 6.1% and 1.5%, respectively.