Paper‐based microfluidics is characteristic of fluid transportation through spontaneous capillary action of paper and has exhibited great promise for a variety of applications especially for sensing. Furthermore, paper‐based microfluidics enables the design of miniaturized electrochemical devices to be applied in the energy sector, which is especially attractive for the rapid growing market of small size disposable electronics. This review gives a brief summary on the basics of paper chemistry and capillary‐driven microfluidic behavior, and highlights recent advances of paper‐based microfluidics in developing electrochemical sensing devices and miniaturized energy storage/conversion devices. Their structural features, working principles and exemplary applications are comprehensively elaborated and discussed. Additionally, this review also points out the existing challenges and future opportunities of paper‐based microfluidic electronics. Paper‐based microfluidics emerges as a powerful and versatile platform for constructing simple, inexpensive, environmentally‐friendly and high‐performing miniaturized electrochemical devices for various applications. This review summarizes the basics of paper‐based microfluidics and highlights some recent advances of paper‐based microfluidics in developing electrochemical sensing and energy storage/conversion devices. Their structural features, working principle and exemplary applications are comprehensively elaborated and discussed. This review also points out the existing challenges and future opportunities of paper‐based microfluidic electronics.