A method for reducing the amount of computations required for multilayer-based progressive fine granular scalability (PFGS) algorithm and a video coding method and apparatus employing the same method are provided. The video coding method supporting fine granular scalability (FGS) includes obtaining a predicted image for a current frame using a motion vector estimated at predetermined accuracy, quantizing a residual between the current frame and the predicted image, inversely quantizing the quantized residual, and generating a reconstructed image for the current frame, performing motion compensation on an FGS layer reference frame and a base layer reference frame using the estimated motion vector, calculating a residual between the motion-compensated FGS layer reference frame and the motion-compensated base layer reference frame, subtracting the reconstructed image for the current frame and the calculated residual from the current frame, and encoding the result of subtraction.