Abstract: Experiments of a large turning angle linear compressor cascade with air injection slot were carried out,and detailed outlet flow field characteristics at design incidence were described in this paper.The results show that air injection through slots decreases the turning and diffusion of compressor cascade,the aerodynamic performance of the cascade also decreases;air injection energizes the low energy fluid near wake,increases the velocity of the wake,thus the size of the wake region reduces significantly,pitch-wise distribution of flow outlet angle becomes more uniform,slot position has great effect on wake especially with slot located near mid-span;multi-slot configurations have greater effect on outlet flow field than one-slot configurations.