Electrogastrography (EGG) appears to be useful method to evaluate the gastric motility as noninvasive approach. However, it is not known what EGG means. The aim of this study is to make clear the meanings of electrical activity recorded dy EGG for gastric motility. EGG recorded by cutaneous electrodes was compared to gastric electromyogram recorded by serosal electrodes and gastric mechanical activity recorded by straingauge transducer in anesthetized and conscious dogs. EGG recordings were preserved when gastric mechanical activity was not recognized. In digestive state, amplitude of EGG, electromyogram and mechanical activity increased significantly (p < 0.01). Significant correlation between amplitude of EGG and amplitude of electromyogram and mechanical activity of antrum were seen (p < 0.01). In interdigestive state, amplitude of EGG in phase 3 increased significantly (p < 0.05) compared to that in phase 1. Significant correlation between amplitude of EGG and amplitude of electromyogram and mechanical activity were seen in phase 2 (p < 0.01). EGG reflected electrical control activity (ECA) and electrical response activity (ERA). EGG recordings showed electromyogram and mechanical activity of gastric antrum. Amplitude of EGG reflected electromyogram and mechanical activity in phase 2 in interdigestive state. EGG waves did not always agree on myoelectrical waves.