Ail efficient red light generation in a periodically poled LiTaQ (PPLT) by extracavity single-pass frequency doubling of a diode-pumped Nd:YVO4 laser at 1342 nm is reported. The sample used in the experiment is 20 mm in length and 14. 77 μm in period. The maximum output power of the 671 nm red laser is 840 mW, when the pump power of 808 nm is 12.3 W. The overall optical-to-optical efficiency is 6.8%. An internal conversion efficiency of 63% is obtained when fundamental power of 1342 nm is 647 mW. The measured effective nonlinear coefficient under the CW mode of the sample is ~4.6 pm/V.