a dielectric ceramic composition which comprises a composition represented by xbao . ynd 2 o 3 . ztio 2 , y 2 o 3 in an amount not more than 15 wt % of the amount of said composition , and al 2 o 3 in an amount not more than 2 wt % of the total amount of the principal components bao , nd 2 o 3 , tio 2 , and y 2 o 3 . and a relative permittivity εr of the dielectric ceramic is not less than 59 , its dielectric loss is 3 × 10 - 4 ˜ 8 × 10 - 4 , and its temperature coefficient of resonant frequency τf may be - 30 ˜+ 10 ppm /° c . this microwave ceramic dielectric will be used for dielectric resonators in the microwave frequency region , microwave ic substrates , and impedance matching of microwave circuits .