Polyadenylation is an important post-transcriptional process that governs mRNA stability and expression. Advancements in direct RNA sequencing in recent years have clarified many aspects of this intricate regulation, revealing the influence of various factors. Here, we used Nanopore Direct RNA Sequencing to investigate the association between genome-wide mRNA poly(A) tail profiles and sexual dimorphism inCaenorhabditis elegans. Our results demonstrate sex-dependent differences in both gene expression and poly(A) tail metabolism. Notably, we discovered that cytoplasmic poly(A) polymerase TENT-5 regulates multiple male-specific transcripts, predominantly encoding putative seminal fluid components with predicted extracellular localization. TENT-5 expression in male-specific tissues, such as seminal vesicle and vas deference, corroborates its functional significance. Intriguingly, despite extensive TENT-5-mediated polyadenylation of male-specific transcripts, males devoid of TENT-5 show no abnormalities in mating behavior, sperm morphology, or fertility. Our findings suggest that TENT-5 plays a role in regulating sex-related processes in males, although the physiological consequences remain to be fully elucidated.