Abstract: To develop a special miniature PSA oxygen concentrator for SARS patients, the effects of operating parameters, such as production duration, purge-to-product ratio, product flowrate, length-to-diameter ratio of the columns and properties of adsorbents, on the product purity and recovery of the miniature PSA oxygen system were experimentally investigated. The experimental results show that, under miniaturization conditions for PSA process, the optimal production duration is 12 s and the purge-to-product ratio is 0.5. The product purity decreases and the recovery increases when the product flowrate increase. When the product purity is above 90%, the product recovery is about 19%. The properties of adsorbent has significant influences on performances. The product purity increases with the length-to-diameter ratio of column increasing and the proper value of the ratio is between 3.7 and 4.0.