The present invention discloses a vehicular network variable frame structure communication method, and also discloses a vehicular network terminal and a vehicular network system for implementing the variable frame structure communication method. The vehicular network variable frame structure communication method reduces a communication time delay by shortening a frame length. Meanwhile, aiming at complicated and variable channel environments of vehicular network and according to a current vehicle running road grade and a road congestion condition, the insertion density and insertion period of the reference signals in subframes are adaptively adjusted, thereby improving the reliability of the entire vehicular network system while reducing the communication time delay.