The utility model discloses a backrest-adjustable telescopic lamp chair which comprises a chair panel and a backrest fixed on the chair panel, and chair legs are arranged at the lower end of the chairpanel; The backrest comprises at least two telescopic rods arranged on the same side edge of the upper end of the chair panel; The telescopic rod comprises a first rod body, a second rod body, a third rod body and a fourth rod body which are movably arranged in sequence from top to bottom; One end, extending into the second rod body, of the first rod body is provided with a limiting rotating piece, and an LED lamp connected with an external power source is arranged between the other ends of the first rod body. Supporting rods are inserted between the third rod body and the fourth rod body which are opposite to each other; And the fourth rod body is fixed on the chair panel. The device can meet different use requirements, and local light source supplement can be carried out.