The present invention discloses a method and a system for realizing three-dimensional location, Wherein the method comprises the following steps: infrared rays transmitted by an infrared reference light source are received by an optical sensor; the position of the optical sensor corresponding to the infrared reference light source is ensured according to the property of the infrared reference light source in an image collected by the optical sensor to realize the three-dimensional corresponding location of the existing optical sensor. In the method and the system for realizing three-dimensional location, the position of the optical sensor corresponding to the infrared reference light source is ensured according to the property of the infrared reference light source in an image collected by the optical sensor, so not only the realization is simple, but also the cost is low compared with the prior art, a good location function can be provided to the application scene (for example, plausibility video) of corresponding location, and the experience of users is greatly improved.