The invention relates to a transparent soil test device for simulating instability of tunnel excavation face, comprising a transparent model box for containing transparent soil and a pipeline for simulating tunnels in construction, wherein one end of the pipeline stretches into the model box, and one end of the pipeline stretches out of the model box. The device is characterized in that the end ofthe pipeline which stretches into the model box is kept closed and relaxed through a rubber film; a pressure gauge is arranged on the pipeline and connected with an air compressor through a hose provided with a check valve; a cross laser for generating transverse and longitudinal laser sections is fixed above the model box; and a camera is fixed to the periphery of the model box, and images shotby the camera are sent to a computer. According to the transparent soil test device for simulating instability of tunnel excavation face, the device can be used for dynamically simulating an occurrence process of instability damage of the excavation face, and researching a number of factors affecting the stability of the excavation face.