The invention discloses a speech language classifying method based on a CNN and GRU fused deep neural network. The method comprises the following steps that S1, source audio data of a server is obtained, audio preprocessing is conducted, and the source audio data is cut; S2, audio data file information is read, and an audio data inventory CSV file is generated; S3, an audio data file is subjectedto short-time Fourier transformation, and two-dimensional speech spectrums associated with time and frequency domains of expansion of a series of frequency spectrum functions obtained after speech signal time domains are analyzed are obtained; S4, a model is built; S5, two-dimensional speech spectrum image data is input into the CNN and GRU fused speech language classifying deep neural network model, and language classification data is classified and output; S6, the language classification data and source audio data file information are stored. By means of the method, the problem about speechlanguage classification is solved, the method has the advantages of being automatic, high in identification rate, high in robustness, low in cost, high in portability and the like, and the business connection with a third-party system can be facilitated.