Abstract: Provided is an OLED device and a manufacturing method thereof. The OLED device includes: a flexible substrate having signal electrodes embedded on a surface of one side of the flexible substrate and a thin film transistor layer and a pixel unit layer prepared on a surface of the other side; both a first driving chip and a flexible circuit board are disposed on a back surface of the flexible substrate; signal traces in the thin film transistor layer and the pixel unit layer are connected to corresponding signal electrodes through vias, and the signal electrodes are connected to the first driving chip.