The behavior recognition network based on 2D convolutional usually integrates classification results of multiple video frames to recognize different behaviors, but it can′t extract space-time feature using the 2D convolution kernels. To solve this problem, MTSC (multi time-scale convolution) was proposed based on TSM(temporal shift module), which contained convolution kernels of different scales to fuse the space-time feature from different time scales. By controlling the position that inserting MTSC into ResNet50 network and the parameter setting of MTSC, the optimal behavior recognition network based on MTSC was discussed. Using the PyTorch training model, an experimental study was conducted on a large open source dataset, Something-Something v2. The results show that the behavior recognition network based on MTSC achieves 59.47% Top-1 accuracy, and outperform TSM and other behavior recognition networks.