E2F3 is an important member of E2F transcription factors and has been involved in carcinogenesis. So far, little is known on porcine E2F3. Here, we cloned the complete coding sequence (CDS) of E2F3b and identified seven alternatively spliced transcripts in pigs using molecular biology technique for the first time. The CDS of the canonical transcripts (named V1) of porcine E2F3b is 1023 bp in length, and showed 93.35% and 90.62% identities with the homologues from human and mouse, respectively. The splicing variants were produced by exon skipping, alternative 5’ and 3’ splice sites alone or in combination. Minigene analysis showed that the splicing of porcine E2F3b is complicated. E2F3b isoforms are expressed in all tissues studied with high level in spleen and muscle. Both of isoforms V1 and 2, containing functional domains of E2Fs, were localized throughout cells. No functional nuclear localization sequence and export signal were characterized through site-directed mutagenesis analysis, although their existence was predicted by bioinformatic methods. The results increase our knowledge of E2F3b mRNA diversity and provide basis for in-depth functional research.