In this study, microorganisms (named B111) were immobilized on polyvinyl alcohol microspheres prepared by the inverse suspension crosslinked method. The biodegradation of bisphenol A (BPA) and 4-hydroxybenzaldehyde, a degradation product of BPA, by free and immobilized B111 was investigated. The BPA degradation studies were carried out at initial BPA concentrations ranging from 25 to 150?mg·L?1. The affinity constant Ks and maximum degradation rate Rmax were 98.3?mg·L?1 and 19.7?mg·mg?1VSS·d?1 for free B111, as well as 87.2?mg·L?1 and 21.1?mg·mg?1VSS·d?1 for immobilized B111, respectively. 16S rDNA gene sequence analyses confirmed that the dominant genera were Pseudomonas and Brevundimonas for BPA biodegradation in microorganisms B111.