Abstract: Objective To study the mechanism underlying attentional biases toward event-related potential (ERP) in patients chronic lumbocrural pain. Methods Sixteen patients with chronic lumbocrural pain served as an experimental group and 16 healthy subjects served as a control group in this study. Their responses to the neutral, painful and threatening words and the ERP on 32-lead ECG were recorded with a NeuroScan workstation. Results The response time was longer to pain-related words than to neutral words and the P200 amplitude value of threatening words was significantly higher than that of neural words in patients with chronic lumbocrural pain. Conclusion Attentional biases toward pain- related information can be found in patients with chronic lumbocrural pain, which may be related with their emotional control process.