ABSTRACT: The epididymis is essential for the acquisition of sperm fertilizing ability and forward motility. After vasectomy, the flux and composition of the epididymal fluid are modified, causing possible sequelae to the occluded excurrent duct. Some of these sequelae may not be reversible following vasovasostomy, affecting sperm physiology and their fertilizing ability. We previously demonstrated that the epididymal expression in men of a major glycoprotein secreted by the epididymis, cysteine-rich secretory protein 1 (CRISP1), and its encoding mRNA are affected by vasectomy. In this study we showed that following vasectomy, the increased level of CRISP1 is not due to a secretory defect but to its accumulation in the intraluminal compartment of the cauda epididymidis. Western blot analyses were performed to determine the amount of CRISP1 associated with spermatozoa of men who had undergone surgical vasectomy reversal. Spermatozoa of vasovasostomized men are characterized by a significant increase (P < .05) in CRISP1 levels when compared with normal donors. There was no linear correlation between CRISP1 levels and the period of time elapsed between vasectomy and vasovasostomy. CRISP1 was also present in seminal plasma of normal and vasovasostomized men, but not in vasectomized individuals. The soluble concentration of CRISP1 was significantly higher (P < .05) in seminal plasma of vasovasostomized men when compared with normal men. Knowing that one of the proposed functions of CRISP1 is to modulate sperm capacitation, we evaluated the level of tyrosine protein phosphorylation of 2 AXAP proteins of the fibrous sheath, p81 and p105. Spermatozoa of vasovasostomized men were characterized by a 50% increase of protein tyrosine phosphorylation when compared to spermatozoa of normal men (P < .05). Our results are discussed with regard to the fertilizing ability of ejaculated spermatozoa of some vasovasostomized men.