This study aims to investigate the effects of three single nucleotide (SNPs) polymorphisms of the MBL1 gene on subclinical mastitis for Holstein cows. For this study, a total of 151 Holstein cows were selected in their third lactation. The subclinical mastitis conditions were determined using the California Mastitis Test (CMT). Genotyping was carried out with the PCR-RFLP method. The results revealed that the wild-type allele frequencies were 0.72 (G allele), 0.40 (G allele), and 0.37 (T allele) for 1252 G>A, 2534 G>A, and 2569 T>C SNPs, respectively. Among the investigated SNPs, only the 1252 G>A SNP was not found in Hardy-Weinberg equilibrium. The effects of SNPs on subclinical mastitis were modeled using multiple logistic regression analysis. The established model can identify cows with subclinical mastitis with a separation efficiency of 62.3%. It was thought that 1252 G>A and 2534 G>A SNPs may affect subclinical mastitis rates.