The objective of the study was to determine the relationship between the mRNA expression levels of sperm phospholipids hydroperoxide glutathione peroxidase (PHGPx) and heparin-binding protein (HBP), and in-vivo fertility in boars. The farrowing rate was not correlated with litter size. Sperm PHGPx mRNA expression level of the larger litter size (over 10) group $(2,414.7{pm}400.7)$ was high that of smaller litter size (below 8) group $(1,875.8{pm}311.2)$. Sperm HBP mRNA expression level was also higher in the larger litter size $(2,255.9{pm}360.8)$ group than the smaller litter size $(2,155.4{pm}378.0)$. However, significant differences were not observed. Sperm PHGPx mRNA level was correlated positively with litter size (r=0.206). Because the expression levels of PHGPx and HBP are not strongly correlated with in-vivo fertility, PHGPx and HBP can not be considered a predictive measure for fertility in boars.