Provided are a method of generating a respiratory status classifier and a method of determining respiratory status. The method of generating a respiratory status classifier includes segmenting collected respiratory signals according to respiratory cycles, acquiring data pairs of a calculated power spectrum of frequency components and a designated respiratory status indication value for a plurality of cycle-specific respiratory signals selected from among the segmented cycle-specific respiratory signals, selecting specific frequency components from among the frequency components, inputting data pairs of a power spectrum and a designated respiratory status indication value corresponding to the specific frequency components to a respiratory status classifier, and training the respiratory status classifier according to output values from the classifier.