A new spike detection method is proposed in order to detect the overlapped spikes. In order to avoid missing overlapped spikes, the method adds threshold detection based on window detection method. Moreover, nonlinear energy operator is introduced to make the method strong even under low signal-to-noise ratio situation. In addition, the method solves the repeated detection problem by estimating slopes. Experiments show that the method is good for any occasion whatever the low signal-to-noise ratio or baseline wander. Especially for the overlapped spikes detection, it has much lower false-negative-rate than other traditional detection methods.