The invention provides a diesel engine detection method and device. The method comprises the steps that running parameters of a diesel engine are obtained and at least include the engine rotation speed; the crankcase pressure of the diesel engine is determined at least based on the engine rotation speed, the exhaust back pressure of the diesel engine is determined at least based on the engine rotation speed, and the rotation speed change rate of the diesel engine is calculated according to the rotation speed of the engine; and whether the diesel engine is in a cylinder score state or not is judged at least based on the crankcase pressure, the exhaust back pressure and the rotation speed change rate. On the basis of the diesel engine detection method and device, whether cylinder score happens to the diesel engine or not can be rapidly judged under the situation that no sensor is additionally added, further damage of the diesel engine is prevented, timeliness of the service is improved,and the customer satisfaction degree is improved.