Milk mainly composed of water, proteins (casein), sugar (lactose), fat and minerals (calcium and phosphorus). Also milk contains a few pigment, enzymes, vitamins, phospholipids and gas. There are close relationship between grazieries feed composition, milk products quality and community health level. In this study used feed composition were examined in ten traditional and industrial grazieries in Markazi Province, Iran in the years 2009 and 2010. Also ash, casein and fat weight (gr/lit) of obtained milk samples from these grazieries were seasonally measured. Data analyzed using EXCEL and SPSS. Results showed the most feed composition materials were Zea Myse, Medicago, Hordeum, Soya, Food complement and NaCl. Maximum and minimum milk ash weights were 37 in spring and 2 gr/lit in Autumn respectively. The highest and lowest casein levels were 123.5 and 55 gr/lit in Autumn and Spring respectively. 130.1 in Autumn and 23 in Spring were maximum and minimum gr/lit milk fat weight respectively in studied milk samples. Statistical analysis showed close and strong negative and positive correlations between studied milk parameters and consumed feed composition in grazieries. Negative correlation between milk casein and fat in winter and positive correlations between spring milk ash weight and concentrate. Also spring milk fat weight had positive correlation with and Zea Myse (ZM) and Hordeum (H) (P<0.01). The results show a reserved relationship between winter milk casein and fat. Milk composition depends on cow diets by the reason unequal seasonal feed in Iranian grazieries. Therefore, quality control of consumer milks always is needed and is effective on community health.