Ultrasonic velocity and absorption measurement were made at 3 MHz in ovalbumin, conalbumin and ovomucoid which were protein constituent of egg white, over temperature range 10∼95℃ using pulse echo overlap method. The gelation process caused by heat was studied by the change in the velocity and absorption. The gelation temperatures of the ovalbumin and conalbumin proteins were 70℃ and 50℃, respectively. However the gelation of the ovomucoid protein did not occur in gelation under experimental temperature condition. The change in the absorption and velocity due to gelation was observed as a function of time at aging temperatures ranging front 50∼95℃ for conalbumin, 70∼95℃ for ovalbumin. The experimental results showed that the change were prominent at 55℃ in conalbumin, 75℃ in ovalbumin. Hysteresis phenomenon was also observed by varying the aging temperatures as a parameter. This phenomenon is associated with the memorizing effect of the network structure of protein in gel. It was demonstrated that the ultrasonic technique was useful for monitoring the gelation process.