The invention relates to a tunable laser for outputting non-polarized light. The tunable laser is mainly and technically characterized by comprising a first reflection mirror, a broadband laser gain medium, a tunable Fabry-Perot filter, a tunable acousto-optic filter, a second reflection mirror, a third reflection mirror and a laser control circuit, wherein a broadband light beam sent from the broadband laser gain medium can be filtered by the tunable Fabry-Perot filter and then is filtered by the tunable acousto-optic filter; a first-grade diffraction light beam is divided into two beams of polarized light with vertical polarized states; and a zero-grade diffraction light beam of the tunable acousto-optic filter is taken as an output light beam of the laser device. According to the tunable laser disclosed by the invention, continuous, the continuous, rapid and precise tuning can be performed on the output light of the laser in a wide spectral range; and the tunable laser has the characteristics of absence of mechanical movement parts, high electronic tuning speed, stable and reliable performance, small size, easiness in production and the like, and can be widely applied to the fields of lasers, optical tests, optical fiber communication, biological and medical instruments, optical fiber sensor networks and the like.