This study was undertaken to evaluate the effect of rabbit peritioneal fluid(rPF) on in vitro maturtion of porcine follicular oocytes. From does 20h after hCG injection, rPF was aspirated aseptically at laparatomy, and then centrifuged, filtrated, and preincubated immediately for 12h. Porcine follicular oocytes isolated from ovaries of slaughtered animals were incubated in TCM-HEPES＋10% FCS, TCM-HEPES＋rPF(v/v, 50/50), or rPE only and examined the nuclear maturation after aceto-orcein or hochest staining. After identifying the optimal incubation time, this experiment was repeated for 5 times. Under the TCM-HEPES containing hormones and serum codition, the time range of porcine follicular oocyte maturation was 38 to 44 hours and the optimal time of maturation of follicular oocyte in vitro was 42 hour cultivation, respectively. The maturatin rates(89.4% and 92.7%) of porcine follicular oocytes cultured in the media with 50% rPF or only rPF were signifciantly higher thanthat (84.6%) of oocytes cultured with TCM-HEPES, respectively. These results suggest that the unknown components(s) of rPF promoted in vitro maturation of porcine follicular oocytes.