This study was carried out to determine relationship between california mastitis test (CMT), somatic cell count (SCC), electrical conductivity (EC) of milk, bacteriological examinations and size of the superficial supramammary lymph nodes in subclinical mastitis of lactating cows. Milk samples collected from 1184 quarters of 296 Holstein cows between 3-9 aged in Saray farms in Kayseri were used as study materials. The ultrasonographical examination of the superficial supramammary lymph nodes of cows was caried out by using a 7.5 MHz linear transducer (Honda Vet-1500 Ultrasound). The horizontal lenght of lymph node was measured at hyperechoic line by transducer. A positive correlation (P<0.01) was found between the size of the superficial supramammary lymph nodes and SCC. The most frequently isolated microorganism was Staphylococcus aureus in bacteriological examinations. In conclusion, although SCC, CMT and EC results are consistent with the ultrasonographic appearance of the superficial supramammary lymph nodes, it is not possible to use the lymph nodes as a solely diagnostic method because of the largened lymph nodes beforehand occured mastitis.