Objective CatSper1 is a sperm-specific voltage-gated Ca2+ channel protein that plays an essential rolein spermatogenesis and fertilization. We analyzed the expression regulation pattern, sequence characteristics, and potentialbiological function of CatSper1 gene of Banna mini-pig inbred (BMI) line. Methods The testes of adult BMI boars wereused for RNA sequencing (RNA-seq), and the complete coding sequence of CatSper1 was cloned using reverse-transcriptionpolymerase chain reaction. The sequence, structural characteristics, and interacting proteins of CatSper1 wereanalyzed. The lncRNA and miRNA regulatory network of CatSper1 was constructed, and gene ontology function annotationswere carried out using RNA-seq data. Results The average expression level and transcripts per million of CatSper1obtained by RNA-seq was 2817. 5 and 33. 6, respectively. The full-length coding sequence of CatSper1 was 2166 bp (GenBank accession number: OK042306), encoding 721 amino acids. CatSper1 protein contained an Ion_trans conserveddomain of 233 amino acid residues and a conserved transmembrane helix structure related to spermatogenesis. CatSper1protein interacted with 10 proteins related to male reproduction, especially CatSper2-4 of the CatSper family. Ten miRNA sregulated CatSper1 gene by a targeted mode, and 16 and 14 lncRNAs completed with CatSper1 for binding to ssc-miR-1343and ssc-miR-744, respectively. The gene ontology annotation result indicated that the CatSper1 gene plays important rolesin molecular functions, biological processes, and cellular components. Conclusions This study reported the expression CatSper1 in BMI testis, the molecular structure characteristics and expression regulatory network. The fundings will laygroundwork for further research of CatSper1 function in important biological processes such as spermatogenesis, spermcapacitation and acrosome reaction in BMI line.