The combination of 1 μm continuous wave (CW), high power, narrow-linespectrum fiber amplifier and the periodically poled materials with high second harmonic generation efficiency provides a compact and high efficiency approach for wavelength conversion with high beam quality. A polarization maintaining all fiber amplifier with the master-oscillator power amplifier (MOPA) is built. 30 W CW fiber laser is obtained with 0.035 nm linewidth at 1064.25 nm center wavelength. Single-pass, second-harmonic generation of the fiber laser in periodically poled stoichiometric lithium tantalate (PPSLT) made in China is demonstrated. Stabilizing the temperature at 145.6 ℃, 2.1 W green light is achieved at the pump fundamental power of 21.5 W. The effects on the second harmonic generation efficiency produced by temperature, input power density, and Boyd-Kleinman focusing parameter are analysed. Higher power green light can be expected by increasing the fundamental power because the saturation effect is not observed.