The invention relates to a liquid crystal display module and a display detecting circuit thereof. The display detection circuit comprises a module grounding line, a circuit board grounding line, a grounding module, a circuit board testing circuit, an auxiliary detecting line and a resistor R2, wherein the module grounding line is provided on the module body; one end of the circuit board groundingline is electrically connected to one end of the module grounding line, the other end of the circuit board grounding line is provided with a grounding interface, the circuit board grounding line is provided on a flexible circuit board connected to the module body; the grounding module is electrically connected to the circuit board grounding line, the grounding module is disposed on the flexible circuit board; one end of the circuit board test circuit is electrically connected to the other end of the module grounding line, and the other end of the circuit board testing circuit is provided witha test interface. Since the chip driving interface, the test interface, and the grounding interface are all disposed on the flexible circuit board, the module function tester is easily used for detection, thereby improving the detection efficiency of the display detection circuit.