An automatic depression detection method includes the following steps of: inputting audio and video files, wherein the audio and video files contain original data in both audio and video modes; conducting segmentation and feature extraction on the audio and video files to obtain a plurality of audio segment horizontal features and video segment horizontal features; combining segment horizontal features into an audio horizontal feature and a video horizontal feature respectively by utilizing a feature evolution pooling objective function; and conducting attentional computation on the segment horizontal features to obtain a video attention audio feature and an audio attention video feature, splicing the audio horizontal feature, the video horizontal feature, the video attention audio feature and the audio attention video feature to form a multimodal spatio-temporal representation, and inputting the multimodal spatio-temporal representation into support vector regression to predict the depression level of individuals in the input audio and video files.