Thulium-doped orthorhombic gadolinium scandate, Tm:GdScO3, is promising for efficient linear polarized continuous-wave (CW) and passively Q-switched lasers near 2 μm. The polarized characteristics of different lasing propagation were verified by both the emission spectra and the laser experiments. Under diode pumping at 793 nm, linear polarized lasers of electric field direction (E) parallel to a- and b-axis are obtained with the maximum output power of 1.87 W and 2.00 W and with the slope efficiency of 27.5 % and 28.4 %, respectively. Stable passive Q-switching of the Tm:GdScO3 laser using SnS2 is demonstrated for the first time, to the best of our knowledge. With different output couplers, the 1.99 μJ/460 ns pulses at ∼2 μm were achieved with a maximum average output power of 0.175 W and a peak power of 4.32 W. Tm:GdScO3 is promising to be the candidate for 2 μm ultrashort lasers.