Aiming at the problems of the existing vehicle object detection algorithm based on convolutional neural network that cannot effectively adapt to the changes of object scale, self-deformation and complex background, a new vehicle detection algorithm based on multi-scale context convolution features is proposed. The algorithm firstly used feature pyramid network to obtain feature maps at multiple scales, and candidate target regions are located by region proposal network in feature maps at each scale, and then introduced the context information of the candidate object regions, fused the context information with the multi-scale object features. Finally the multi-task learning is used to predict the position and type of vehicle object. Experimental results show that compared with many detection algorithms, the proposed algorithm has stronger robustness and accuracy.