Natural food coloring is biopigment produced by Monascus purpureus. It can be widely used in many industries such as foods, pharmaceutics and cosmetics. Induced mutation of Monascus purpureus TISTR 3002 and TISTR 3385 was experimented by using ultrasonic wave at 28 oC, 45 kHz for 2 min to develop an efficiency food coloring mutant for 4 generations. Red pigment stability to temperatures, pH range and solvents was also evaluated. Preliminary study of the growth rates on PDA was found that TISTR 3180, TISTR 3090, TISTR 3002, TISTR 3385 and TISTR 3541 were 5.241, 4.950, 4.863, 4.746 and 4.670 mm/day, respectively. Results showed that these fungi produced yellow, orange and red pigment at the maximum wavelength of 340, 440 and 480 nm in that order. Temperature stability of red pigment exhibited that a G2 mutant of TISTR 3002 was the most stable generation at 78 oC when compared to G3, G1 and G4 with the decrease of stability more than G0 : 3.27, 1.94, 1.93 and 1.44 times, respectively. Red color of TISTR 3002 G4 mutant was more stable at pH 7 than G3 and G1 with the values of 8.62, 3.10 and 1.50 times. The resistance to solvent, distilled water, degradation results revealed that TISTR 3385 G1, G2, G3 and G4 mutant when compared to G0 at the value equivalent to 1 time. In terms of the comparison on the generation effect to color production, statistical analysis showed that TISTR 3002 G2 mutant produced significantly higher color than wild type about 2 times (p = 0.007), while TISTR 3385 G4, G3, G1 and G2 mutants yielded 2.17, 1.71, 1.58 and 1.49 times with the p-values of 0.003, 0.016, 0.025 and 0.033, respectively.