The aim of this study was to determine the effect of germination process (i.e., soaking time and temperature, germination time, and ultrasound treatment) on the germination rate of germinated paddy. In addition, gamma-aminobutyric acid (GABA) content, and morphology of starch granule of dehulled germinated paddy (germinated brown rice, GB) were characterized. The results showed that extended soaking time from 4 h to 24 h insignificantly increased the germination rate, and increased soaking temperature from 30°C to 40°C had no effect on germination rate (p>0.05). However, extended germination time from 14 h to 48 h significantly improved the germination rate, given soaking time and temperature of 2-8 h at 30°C (p<0.05). Ultrasound treatment for 15 min after 8 h soaking significantly increased the germination rate of 24 h germination, compared with non-ultrasound and ultrasound treatment for 15 min before 8 h soaking. Meanwhile, extended germination time to 48 h, the ultrasound treatment had no effect on the germination rate (p>0.05). The germination process did not affect the morphology of the GB starch granule, compared with brown rice (BR). However, GaBa content of GB (11.67 mg/l00g) was significantly higher than that of BR (1.08 mg/100g) (p<0.05).