The invention discloses a legionnella selective separation medium. Dyes such as bromothymol blue and bromocresol purple are added to the basic formulation of the basic medium of legionnella BCYE alpha and legionnella selective antibiotics of glycin, vancocin, polymyxin B and actinone are also added. The added dyes produce pigment in the growth process of legionnella; the shape and the color of a colony are beneficial to identifying and distinguishing a target bacterium of the legionnella; the concentrations of the selective antibiotics are added and regulated, the inhibiting capability to non-legionnella and microbial class is enhanced and the inhibiting performance for the legionnella is reduced, thereby enhancing the positive rate for the separation culture of the legionnella; the detection cost is reduced and the legionnella selective separation medium is economic and practical and is convenient for popularization and application for clinical and health and epidemic prevention departments.