A method is disclosed for checking model planes entering into a dive, as well as an anti-dive method and apparatus. The method of checking planes includes installation of a first optical sensor in the upper part of the plane, with installation angle upwardly intersecting with the front of the plane at α degrees, that checks light intensity and outputs a first checked optical signal; installation of a second optical sensor in the bottom part of the plane, with its installation angle downwardly intersecting with the back of the plane at β degrees, which checks light intensity and outputs a second checked optical signal. A comparison is made between the first and second checked optical signals, and when the difference in light intensity is smaller than a threshold, a warning signal is sent out indicating that the plane has entered into a dive.