As one of the important microorganisms in the human body， lactic acid bacteria （LAB） play a probiotic role in the intestine. However， the growth and colonization of LAB are affected by its poor environmental tolerance. Therefore， it is important to explore the microencapsulation of LAB to improve its environmental tolerance. The strain of Pediococcus pentosaceus 10-a-1 with high tolerance and adsorption capacity of lead was used in the research. Sodium alginate microcapsules were prepared by internal emulsification and the technological conditions were optimized. The optimum technological parameters were determined by single factor test and orthogonal test. On this basis， chitosan was used for secondary embedding. The characteristics of the two microcapsules were compared. The results showed optimum process conditions were determined， sodium alginate concentration was 3%， water-oil ratio at 30∶120， calcium acid ratio at 3∶1， stirring speed was 600 r/min， the ratio of calcium and gel was 1.5∶9. Under the optimized conditions， the encapsulation rate of the sodium alginate microcapsules reached 86.3%. After the encapsulation of sodium alginate microcapsules by chitosan， the embedding rate of microcapsules decreased to 65.6%. The characteristics of the two microcapsules was compared， sodium alginate microcapsules released more quickly than sodium alginate-chitosan microcapsules. The sodium alginate- chitosan microcapsules showed better tolerance to gastric and intestinal fluids and resulted in the higher survival rate. The adsorption capacity of lead in sodium alginate-chitosan microcapsules was better. The survival rate of LAB in sodium alginate-chitosan microcapsules was the highest after 28 days of storage at 4 ℃ and 20 ℃， respectively. The microencapsulation technology could significantly improve the tolerance of P. pentosaceus 10-a-1 to adverse environment. Meanwhile， the effect of simulated gastrointestinal fluid treatment on the ability of P. pentosaceus 10-a-1 to adsorb lead could be reduced.