High quality nonlinear infrared crystal material AgGeGaS4 with size 30 mm diameter and 80 mm length was grown via reaction of raw materials AgGaS2 and GeS2 directly. The as-prepared products were characterized with X-ray powder diffraction pattern and their optical properties were studied by spectroscopic transmittance. The absorption coefficient in the region of 6.8-7.8 mu m is as low as 0.02 cm(-1), also, frequency doubling for 2.79, 8 mu m with different lasers was demonstrated successfully. The reaction conditions are easy to be maintained and controlled, which may provide a new method to produce other high-quality AgxGaxGe1-xS2 materials via changing the amount of GeS2. (C) 2008 Elsevier B.V. All rights reserved.