Photodetectors based on anisotropic materials are attracting lots of attention. This research systematically investigates the anisotropic photoresponse of photodetectors based on the two-dimensional WSe₂/MoSe₂ lateral heterostructure through quantum transport simulations. The transport direction is crucial for photocurrent. In the armchair direction, the photocurrent is sensitive to ultraviolet light, while in the zigzag direction, cyan light is significant. The photocurrent magnitude in the zigzag direction is 79 times larger than that in the armchair direction. The extinction ratio (ER) also exhibits strong anisotropy between the two directions. Infrared and visible light have more influence on the ER in the armchair direction, and ultraviolet light is crucial in the zigzag direction. The research provides a promising candidate for directional sensitivity photodetectors.