A total of 116 quarter milk samples were collected aseptically from apparently healthy udders of 29 cows in a dairy farm in Beni-Suef city, Egypt; for detection of subclinical mastitis using California mastitis test (CMT), somatic cell count (SCC), chemical and microbiological examination. Thirteen cows (44.83%) were subclinically mastitic with 27 mastitic quarters (23.28%).The scores of CMT showed 11 quarters (40.74%) as +1 and 16 quarters (59.26%) as +2. The SCC of fore left (FL) quarter milk samples was 4.3×10⁵±1.2×10⁵, while of fore right (FR) quarter milk samples was 3.8×10⁵ ±1.1×10⁵, but for SCC of hind left (HL) quarter milk samples was 2.4×10⁵±9.5×10⁴ and SCC of hind right (HR) quarter milk samples was 2.2×10⁵±7.9×10⁴. The isolated micro-organisms from the examined milk samples were Staphylococcus aureus, Coagulase negative Staphylococci (CNS), Streptococcus spp < /em>, E.coli and Aspergillus fumigatus. The present study assured that the indirect tests of subclinical mastitis are more suitable for selecting cows with intramammary infections for subsequent bacteriological sampling.