Changes in hot-taste component during the after-ripening period of hot pepper fruit were surveyed and summarized as follows; (1) Capsaicinoid contents were steadily increased as the after-ripening proceeded when physiological activity of the sample was suppressed during each stage of the ripening with the vacuum dry freezing. (2) It was assumed by determining phenylalanine contents and activities of phenylalanine ammonialyase to see synthetical process of capsaicin in the metabolic part of vanillylamine that there is a gradual synthesis and accumulation of capsaicin during the after-ripening period. (3) Lignin-like substances, as in the case of capsaicinoid, showed a steady increase during the after-ripening period. (4) The contents of polyphenolic compounds and polyphenol oxidase activity were higher with low temperature treatment.