This paper describes the realization of both leakage magnetic flux reduction and temperature distribution improvement about an induction heating (IH) cooking heater. This heater has a problem that the distribution of temperature at the bottom of a pan doesn’t become uniform. In addition，the health harmfulness is feared widely，because there is a leakage magnetic flux. In this study，these two points were improved by adding center coil and ferrite core at the center of heating coil. Density of magnetic flux at the center of heating coil has been increased by 4.98 times. As a result，distribution of temperature at the center of metal load has been improved successfully. For the sake of reducing leakage magnetic flux，a coil whose winding direction is in the opposite direction，is set up at the outer edge of the heating coil. This structure brings excellent results：reduction of the leakage magnetic flux，and prevention of aggravating heating characteristic.

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