Abstract: Output characteristics of continuous wave(CW)orange-red laser with all-solid wavelength tunable based on composite cavity structure are introduced. Composite cavity is composed of an s-polarized signal singly resonant optical parametric oscillator (SRO) using an MgO-doped periodically-poled LiNbO3 (MgO: PPLN) crystal and a p-polarized 1 062.9 nm fundamental frequency light cavity. Independent oscillations of signal light pumped by an s-polarized 1 062.9 nm laser and p-polarized 1062.9 nm fundamental frequency are generated in respective cavity, which produces orange-red laser using a type-Ⅱ critical phase-matched KTP crystal in intracavity sum-frequency generation process. When tuning temperature of MgO:PPLN crystal rises from 30℃ to 200℃, CW orange-red laser beams are obtained with tunable wavelengths from 620.2 nm to 628.9 nm based on wavelength red-shift of s-polarized signal light, corresponding to a measured waveband of mid-infrared idler light from 3 714.2 nm to 3 438.3 nm. At minimum temperature of 30℃, maximum CW output power of orange-red laser is obtained to be 2.0 W at 620.2 nm, corresponding to CW output power of idler light is 2.9 W at 3 714.2 nm.