This study was focused evaluating the effect of heparin binding proteins (HBP) on in vitro capacitation and acrosome reaction (AR) in Beetalbucks. HBP were purified from pooled seminal plasma of six bucks to evaluate their effect on in vitro capacitation. Semen, washed twice with TALP medium was incubated in TALP, supplemented with glucose, BSA, heparin and HBP for 6 hrs at 37°. A control was also run without HBP. Incubated samples were evaluated for motility, viability, acrosome reaction and inner mitochondrial membrane potential (IMMP) after every 2 hrs. Standardization of HBP concentration on in vitro acrosome reaction revealed 150 μg/ml HBP as an optimum dose. Based on sperm parameters, six bucks were divided into two groups i.e. G-I (> 80% motility) and G-II (<80% motility).There was a significant (p<0.05) decrease in individual motility, viability and high IMMP from zero to six hrs of incubation in both control and HBP treated samples of both groups. A significant (p<0.05) increase in acrosome reaction and medium IMMP was noticeable in control and HBP treated samples with an increase in incubation time. In Vitro induced AR was also significantly (p<0.05) higher in HBP treated samples compared to control in both groups at 4 hrs and 6 hrs of incubation. However, Effect of buck on in vitro capacitation and AR was noticeable in both control and HBP treated samples of G-I and G-II. A non-significant (p>0.05) increase in LPO during capacitation and AR was also observed. This study concluded that SP-HBP enhanced the rate of in vitro AR in beetal bucks.