BACKGROUND: There is a great debate but little research addressing the cell suspension obtained from the digested mantle tissues can effective amplify and form pearl sac in vitro, thus producing pearl. OBJECTIVE: To establish an effective technique and method of in vitro separation and culture of mantle of the pearl oyster (Pinctada martensii), and to determine the optimal method of forming pearl sac with the intact structure and secretion function, thus producing pearl. DESIGN, TIME AND SETTING: Single sample observation was performed at the School of Basic Medicine, Guangxi Traditional Chinese Medical University, between August and December in 2008. MATERIALS: Pearl oyster (Pinctada martensii) aged 1.0 2.0 years, were offered by Yingpan Pearl Industrial Co., Ltd. Of Beihai City, China; the self-modified marine shellfish balanced salt solution; the self-prepared concha pteriae serum and concha pteriae body fluid; keratinocyte growth factor was purchased from Sigma, USA. METHODS: The mantle of pearl oyster (Pinctada martensii) was digested with 2.5 g/L trypsin, the harvested cells were cultured using M199 medium containing 10% fetal bovine serum and supplemented with 10 μg/L keratinocyte growth factor, 10% self-prepared concha pteriae serum and concha pteriae body fluid. The cultivation was performed for 30 days. MAIN OUTCOME MEASURES: Cell growth characteristics and growth state. RESULTS: The pearl mantle epithelial cells cultured in vitro were shown to proliferate rapidly, secrete productively, and the muscle cells showed a great proliferation, finally encapsulated the mantle epithelial cells to form pear sac with the intact structure and strong secretion function. CONCLUSION: Using the modified culture technology and culture system, the addition of keratinocyte growth factor can obtain the well growing and secreting pearl sac during in vitro culture of mantle cells.