The invention discloses a method for detecting the oil level of engine oil based on ultrasonic 
waves, which comprises the following steps: step S10, after an automobile is powered on, controlling an electronic engine oil sensor to send ultrasonic 
waves into an engine oil measuring tube and receive echoes; step S11, calculating the oil level of the engine oil in the measuring tube according to the 
propagation time of the ultrasonic 
waves received and transmitted by the electronic engine oil sensor; S12, according to the currently measured oil level, determining the current base engine oil amount through measurement reference parameters pre-calibrated by the base rack; S13, recognizing the current working condition of the vehicle, 
processing and correcting the current basic engine oil amount through a 
processing strategy corresponding to the current working condition of the vehicle, and finally outputting a stable actual engine oil amount 
signal; and S14, sending the actual engine oil quantity 
signal to an instrument for displaying and reminding. The invention further discloses a corresponding 
system. According to the invention, engine oil quantity detection can be carried out under various working conditions, corresponding correction is carried out, the measurement accuracy is improved, and the application scene is widened.