A pitch detection method and appartus are provided. The pitch detection method includes anlyzing an externally input digital signal into frequency components and detecting a pitch candidate based on the frequency components; comparing an error range for the pitch candidate with an error range, which is calculated using the error range or the result of performing autocorrelation on an autocorrelation range, which is calculated using the error range for the pitch candidate, permorming autocorrelation on the digital signal in a predetermined time range when the error range for the result of autocorrelation is less than or equal to the range for the pitch candidate; and determining a pitch within an intersection between a frequency range obtained using frequency analysis and a frequency range, in which an autocorrelation value is largest, as a final pitch. Accordingly, an error range for a pitch detection result is reduced by sequentially performing frequency analysis and autocorrelation with respect to an externally input digita