Abstract: This experiment was conducted to obtain sequence of 2, 4 -dienoyl -CoA reductase 1 (DECR1), and to study its prokaryotic expression. By Reverse Transcription PCR and Rapid Amplification of cDNA Ends (RACE), the fulllength cDNA of DECR1 was cloned from Mashen pig liver, and inserted into the expression vector pET-32a+. After confirmation by the sequencing and restriction enzyme analysis, the recombinant plasmid was transformed into E. coli BL21. The results indicated that the cDNA of pig DECR1 contained 2 352 nucleotides, including a 987 bp open reading frame (ORF) flanked by a 53 bp 5′-UTR and a 1 312 bp 3′-UTR. Pig DECR1 CDS encoded 328 amino acid residues, which shared 99%, 88%, 88%, 87%, 87%, 87%, 87% and 83% identity with those of Sus scrofa (predicted), Bos taurus, Homo sapiens, Macaca mulatta, Pan troglodytes, Equus caballus, Canis and Mus musculus, respectively. SDS-PAGE results showed that the recombinant protein was expressed and then the expression level reached the highest level after induced for four hours. Western blot analysis indicated that the molecular weight of the expressed protein was the same as predicted size of approximately 35 ku. Collectively these data provided the important information for further studying the physiological functions and molecular mechanism of pig DECR1 gene.