The invention provides a method and a device for realizing audio pitch shifting. The method comprises the following steps of: determining a pitch shifting factor alpha according to a received pitch shifting mode d and a numerator q and a denominator p after the pitch shifting factor alpha is expressed in the form of a fraction; for each audio signal input frame X, performing re-sampling and filtering on time domain on the audio signal input frame X based on q and p; judging an unvoiced sound and a voiced sound for the re-sampled and filtered audio signal input frame X and determining the pitch period of the re-sampled and filtered audio signal input frame X; determining whether the tone needs to be raised or fell according to the pitch shifting mode d; if the tone needs to be raised, performing data replication on the re-sampled and filtered audio signal input frame X with the pitch period as a unit based on the judgment results of the unvoiced sound and the voiced sound; and if the tone needs to be fell, performing data deletion on the re-sampled and filtered audio signal input frame X with the pitch period as a unit based on the judgment results of the unvoiced sound and the voiced sound. By using the scheme of the invention, the raising or falling of the tone can be effectively realized.