A method and apparatus for channel decoding in a communication system using a Low-Density Parity-Check (LDPC) code is provided. The method includes demodulating a signal transmitted from a transmitter; determining if there are any punctured parity bits in the demodulated signal; determining positions of the punctured parity bits by estimating information about a puncturing pattern when there are punctured parity bits; and decoding data using the positions of the punctured parity bits, wherein the information about the puncturing pattern includes a puncturing pattern obtained by considering a modulation scheme.