Implantable electrode-based in vivo electrochemical sensing research has consistently played a pivotal role in driving advancements in analytical methods within the field of neurochemical research. The intricacies of brain structures and the real-time nature of various physiological activities impose rigorous demands on analytical approaches. High specificity, elevated sensitivity, robust interference resistance, and favorable biocompatibility are essential prerequisites for in situ analysis in living systems. With the development of novel functional materials and advancements in electrochemical research methodologies, there has been significant progress in the field of in vivo electrochemical analysis employing implantable electrodes. Nonetheless, this field continues to encounter a series of challenges. This article reviews the current applications of implantable electrodes, such as enzyme-modified electrodes, aptamer-modified electrodes, ion-selective electrodes, liquid-liquid interface-based electrodes, and ion current rectifying electrodes in the field of in vivo electrochemical sensing, as well as the major progress in the research of their key properties such as biocompatibility and sensitivity. The intention is to offer valuable insights for future research in precision detection within the intricate environment of the brain.