A Nd:YAG crystal was end-pumped by a fiber-coupled laser diode(FCLD). The four-mirror bow-tie ring cavity with a Faraday rotator and a half wave plate was applied to eliminate the spatial hole-burning effect. A solid etalon was inserted into the cavity to obtain the narrow line width single frequency output. The maximum output was 2 W and the slope efficiency was 37% with 7 W of the incident power. The line width of the single frequency was 50 MHz, and the M2 factor was about 1.2.