Millions of people are affecting by epilepsy due to the unclear pathogenesis. In this paper, we fabricated an implantable microelectrode array for spike patterns and local field potential signals detection in the hippocampus of awake epileptic mice. The abnormal epileptiform electrical signals were recorded when the mice were occurring a seizure. During a seizure, pyramidal neurons with higher amplitude appeared together with interneurons which firing intensively. The abnormal local field potential (LFP) waveform changed from the slow oscillation with low frequency and high amplitude, to the sharp-wave and spike-wave. The oscillation frequency of LFP waveform is low while amplitude is high at the beginning and ending of seizure. On the contrary, in the middle of seizure, frequency is high while amplitude is low. This detection technology provides us an effective method to understand the neuron activities at neuron level.