Abstract: Solid and semiconductor lasers have many advantages, but in the field of precision measurement, He-Ne lasers are still the most commonly used lasers of manufacturing high precision instruments. At the beginning of the warming process, He-Ne lasers went through a instability time of the power, frequency, horizontal mode. This paper comprehensively and integrated report rich intensity tuning curves of He-Ne lasers (General and birefringence dual frequency lasers) covered long-term experiments. As basis for judgment of laser performance, it is used in studies on how to infer laser parameters from the curve. It infer something include: laser's longitudinal mode interval, single or two longitudinal mode bandwidth, the degree of etalon or interference effect, etc.