Technical Abstract: To understand the effect of ultrasonic treated on brown rice, it is important to research the water absorption processing of brown rice before and after ultrasonic treatment. The objective of this study was investigate and modeling water absorption characteristics of brown rice using Peleg’s equation. The brown rice and ultrasonic treated brown rice were soaked into water at 30', 40', 50', 60', 80', 100'. The moisture content of brown rice was recorded until the brown rice was equilibrated. Peleg’s equation was used to model the water absorption below 60', and the water absorption character of brown rice above 60' was also investigated. It revealed that ultrasonic treatment significant accelerate the water absorption properties of brown rice. Peleg’s equation fit the measured moisture data below 60'well, the coefficients of regressions r2=0.996 and there have no significant difference between the measured and predict moisture content (R<5%).