The utility model discloses an installation light is joined in marriage with guide rail, it relates to information and communication's optical cable fusion technical field, light is mixed and is provided with the guide rail draw -in groove, and the internally mounted of guide rail draw -in groove has the guide rail, is provided with the forked tail draw -in groove on the guide rail, and light distribution unit sets up in the forked tail draw -in groove, the utility model discloses can be fast, accurate, simple and convenient, errorless, the safe distribution unit that will be bare puts into light and joins in marriage to improve work efficiency.