A living body detection method, comprising: extracting valid depth data of a target detection object from depth map data containing the target detection object, wherein the valid depth data of the target detection object is valid depth data of a region where the target detection object is located; generating a depth difference histogram based on the valid depth data; and inputting the depth difference histogram into a pre-trained machine learning classifier to obtain a determination result of whether the target detection object is a living body; wherein the step of extracting valid depth data of a target detection object from depth map data containing the target detection object comprises: extracting depth data of the target detection object from the depth map data containing the target detection object in a manner of image segmentation according to a preset depth difference range; determining whether an angle of the extracted depth data on each coordinate plane of a three-dimensional coordinate system is within a preset angle range; if this angle is within the preset angle range, taking the extracted depth data as the valid depth data of the target detection object; otherwise, determining the extracted depth data as invalid depth data of the target detection object, wherein the angle of the extracted depth data on the coordinate plane of the three-dimensional coordinate system is an angle between a plane directly facing the target detection object and the coordinate plane of the three-dimensional coordinate system; wherein an xy plane of the three-dimensional coordinate system is parallel to a plane where a sensor of an image capturing device for acquiring the depth map data is located, and a z-axis of the three-dimensional coordinate system is a main optical axis of the image capturing device. extracting valid depth data of a target detection object from depth map data containing the target detection object, wherein the valid depth data of the target detection object is valid depth data of a region where the target detection object is located; generating a depth difference histogram based on the valid depth data; and inputting the depth difference histogram into a pre-trained machine learning classifier to obtain a determination result of whether the target detection object is a living body; wherein the step of extracting valid depth data of a target detection object from depth map data containing the target detection object comprises: extracting depth data of the target detection object from the depth map data containing the target detection object in a manner of image segmentation according to a preset depth difference range; determining whether an angle of the extracted depth data on each coordinate plane of a three-dimensional coordinate system is within a preset angle range; if this angle is within the preset angle range, taking the extracted depth data as the valid depth data of the target detection object; otherwise, determining the extracted depth data as invalid depth data of the target detection object, wherein the angle of the extracted depth data on the coordinate plane of the three-dimensional coordinate system is an angle between a plane directly facing the target detection object and the coordinate plane of the three-dimensional coordinate system; wherein an xy plane of the three-dimensional coordinate system is parallel to a plane where a sensor of an image capturing device for acquiring the depth map data is located, and a z-axis of the three-dimensional coordinate system is a main optical axis of the image capturing device. extracting depth data of the target detection object from the depth map data containing the target detection object in a manner of image segmentation according to a preset depth difference range; determining whether an angle of the extracted depth data on each coordinate plane of a three-dimensional coordinate system is within a preset angle range; if this angle is within the preset angle range, taking the extracted depth data as the valid depth data of the target detection object; otherwise, determining the extracted depth data as invalid depth data of the target detection object, wherein the angle of the extracted depth data on the coordinate plane of the three-dimensional coordinate system is an angle between a plane directly facing the target detection object and the coordinate plane of the three-dimensional coordinate system; wherein an xy plane of the three-dimensional coordinate system is parallel to a plane where a sensor of an image capturing device for acquiring the depth map data is located, and a z-axis of the three-dimensional coordinate system is a main optical axis of the image capturing device.