Implantable electronic devices have become indispensable tools for biological science research and medical clinical applications. Focusing on the implantable optoelectronic devices and systems, we introduce the material fabrication, technique integration and implantable strategies of various implantable passive and active devices for biomedical applications. The energy and information transmissions in implantable optoelectronic devices are classified. In addition, the examples of typical implantable electronic systems are showcased from the perspective of biomedical research and applications. Current methods and technologies are discussed comprehensively. In addition, the characteristics, future development trend and challenges of various technique schemes are analyzed and summarized when the requirements of practical applications and biocompatibility are considered.