Surface defects in steel manufacturing can compromise product quality and safety. Detecting these diverse and complex defects under industrial conditions is challenging. This paper proposes WSS-YOLO, a YOLOv8-based model, for accurate defect detection on industrial steel. Firstly, the dynamic non-monotonic focusing mechanism based on WIoU loss was employed to focus on anchor boxes with ordinary quality, thereby improving the overall performance of the detector. Secondly, the C2f-DSC module based on dynamic snake convolution is designed to enable the model to adaptively adjust the receptive field. Finally, GSConv and VOV-GSCSP modules are introduced into the neck network to reduce the computational complexity and parameter quantity while ensuring the accuracy of the model. This paper conducts extensive experiments on the public datasets NEU-DET and GC10-DET, achieving mAP of 82.3% and 72.0%, respectively, outperforming other excellent models. Moreover, the effectiveness of the proposed method in industrial defect detection is also validated.