Ten kilogram of commercial fish meal samples were divided into four groups. Each group was packed in a polyethylene bag and stored at 0, 20, 30 and 40◦C for up to 14 weeks. Histamine (mg/100g), water activity (aw), and moisture content (g/kg) were determined at the beginning of each week for up to sixth week excluding fourth week, then at the beginning of 13th and 14th week. Relative humidity (RH) was not measured after samples were initially packed