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Corona discharge was produced in air atmosphere by applying positive and negative high voltage to a needle to investigate the poling effects for two kinds of sol-gel composite materials, Pb(Zr, Ti)O3(PZT)/PZT and Bi4Ti3O12 (BiT)/PZT. Concerning piezoelectric constant d33, only polarity was different. The samples poled by negative corona discharge showed superior temperature durability above certain temperatures even though no significant difference was observed regarding ultrasonic performance characteristics such as center frequency, 6 dB frequency bandwidth. When the pulse voltage supplied by pulser/receiver increased, that difference starting temperature decreased and negative corona poling effect increased. Negative corona discharge poling was effective to improve thermal durability of sol-gel composite ultrasonic transducers when normal pulser/receiver with negative excitation pulse voltage was used for measurements.