The invention discloses a vehicle cross-lane and converse running detection system based on weight measurement, comprising an industrial personal computer, a license plate capturing and recognizing device and dynamic weighing instruments, wherein each of the dynamic weighing instruments is arranged below each lane, wherein waveform data of passing vehicles is collected by means of the respective dynamic weighing instruments, license plate information of the passing vehicles is acquired through the license plate capturing and recognizing device, the industrial personal computer is configured to associate the waveform data of a corresponding vehicle with the license plate information, waveform characteristics of the waveform data between neighboring dynamic weighing instruments are compared to determine whether the corresponding vehicle is driven in a cross-lane manner, and a time sequence of generating waveform signals between weighing units in each dynamic weighing instrument is analyzed to determine whether the corresponding vehicle is driven in a converse running manner. Therefore, according to the vehicle cross-lane and converse running detection system disclosed by the invention, vehicle cross-lane and converse running detection can be realized according to the waveform data produced when vehicles pass the dynamic weighing instruments.