The present invention provides a high-resolution Micro-OLED display module and a manufacturing method thereof. The method for manufacturing the high-resolution Micro-OLED comprises: S1, providing a substrate, and manufacturing light-emitting pixel units on the substrate; S2, encapsulating the light-emitting pixel units by a film encapsulation technique, and forming a film encapsulation layer; S3, manufacturing sub-pixel units on the surface of the film encapsulation layer, and depositing a metal reflective layer between two sub-pixel units which are adjacent to each other; S4, manufacturing a metal oxide layer on the surfaces of the metal reflective layer and the sub-pixel units by a deposition technique, to obtain a high-resolution Micro-OLED matrix; and S5, using a cover plate to encapsulate the high-resolution Micro-OLED matrix produced in step S4, to finish the manufacturing of a high-resolution Micro-OLED.