The rapid development of micro-electronics raises the demand of their power sources to be simplified,miniaturized and highly integratable with other electronics on a chip.In-plane Micro-sized energy stor-age devices (MESDs),which are composed of interdigitated electrodes on a single chip,have aroused par-ticular attentions since they could be easily integrated with other miniaturized electronics,reducing the complexity of overall chip design via removing complex interconnections with bulky power sources.This review highlights the achievements in the device fabrication of in-plane MESDs,as well as their integra-tion and intelligent designs.We also discussed the current challenges and future perspectives for the development of in-plane MESDs.