The prediction error energy in inter-frame prediction with motion compensation is reduced and the coding efficiency is improved. A video encoding method using fractional-accuracy motion compensation includes: a step of generating multiple weighted filter coefficients from multiple interpolation filter sets using weight parameters which designate weight values of interpolation filter coefficients; a step of selecting weighted filter coefficients which minimize prediction error energy in the fractional-accuracy motion compensation from among the weighted filter coefficients; a step of interpolating fractional-accuracy pixels for a reference picture by application of an interpolation filter with the selected weighted filter coefficients and encoding an input picture with the fractional-accuracy motion compensation; and a step of encoding the weight parameters used for generating the selected weighted filter coefficients and the interpolation filter coefficients and adding encoded weight parameters and encoded interpolation filter coefficients to an encoded bitstream.