Preparation conditions for germinated brown rice gruel on its sensory quality were optimized using response surface methodology. Water volume ratio to germinated brown rice significantly affected the sensory quality of germinated brown rice gruel. Sensory quality, such as color, flavour, and overall acceptance increased significantly when milk ratio was increased. R2 of response surface equations were 0.9076, 0.9634, 0.9555, 0.9677 and 0.9769 for color, viscosity, flavour, mouthfeel and overall acceptance respectively (p<0.01). Optimum preparation conditions on overall acceptance for germinated brown rice gruel were: water volume ratio 8.26, cooking time 31.98 min, cooking temperature 95.71$^{circ}C$ and milk ratio 0.54. High correlation was found between viscosity, flavour, mouthfeel, and overall quality.