Although most geckos are carnivorous, a number of examples of occasional observations on plant consumption have been reported in recent years. Moreover, previous research has reported that several Madagascan geckos lick honeydew excreted from planthoppers. Here, I report feeding on tree sap and honeydew by Geckolepis sp., a fish-scale gecko from northwestern Madagascar. Although, in the previous report, the planthopper showed specific abdomen movement after stimulation by a gecko, the planthopper and the gecko in my observation did not show any specific behavioral interaction. Honeydew milking without a specialized behavioral interaction, which was observed in Geckolepis sp., might be the intermediate stage of the evolutionary transition from simple feeding on plant sap to the highly specialized behavioral interaction that enhances honeydew milking.