Recently, more advanced electronic elements become, they consume powerful and radiate more heat in devices. So the most suitable packaging technique is keenly needed. The most important purpose of packaging is to protect devices within a system for a long time and to prevent life of devices from external environments; floating ions such as humidity or sodium, and exposure from ultraviolet rays. In order to study the electrical properties of silicone gels often used as packing material due to the curing condition, volume resistivity and AC breakdown experiment are performed. Specimens are made up at several cured times and temperatures condition ; 0.5[H], 1[H] and 2[H] at 100[$^{circ}C$], 125[$^{circ}C$], 150[$^{circ}C$], 160[$^{circ}C$], 170[$^{circ}C$] and 180[$^{circ}C$]. It is confirmed that from volume resistivity experiment liquid silicone become get state at 90~100 [$^{circ}C$] and cured specimen for 1~2[H] at 170[$^{circ}C$] are superior in electrical properties.