An encoding apparatus and an encoding method, a decoding apparatus and a decoding method, a recording medium, and a program suitable for encoding image signals with a higher compression ratio for transmission or accumulation. In an arithmetic coding section, from among the syntax elements of input image compression information, the frame/field flag is first encoded by a frame/field flag context model. When the macroblock to be processed is subjected to frame-based encoding, a frame-based context model, specified in the current H.26L standard, is applied. On the other hand, when the macroblock to be processed is subjected to field-based encoding, a field-based context model is applied for the syntax elements described below. The present invention is applied to an encoder for encoding image information and a decoder for decoding image information.