The article provides a comprehensive review of fiber-based wearable electronics, focusing on materials, fabrication techniques, device structures, and applications. Fiber-based structures are highly desirable for wearable electronics due to their lightweight, long-lasting, flexible, and conformable properties. The advancement of nanotechnology has enabled the integration of electronic functions directly onto or inside single fibers, which are typically several to tens of microns thick. However, maintaining these functions during wear and deformation remains a significant challenge. The review covers the performance requirements of fiber-based wearable electronic products, emphasizing the correlation between materials, fiber/textile structures, and electronic and mechanical functionalities. It discusses the limitations of current materials and fabrication techniques, particularly in terms of manufacturability and practicality, and highlights the need for further scientific understanding to overcome these challenges. Key topics include: 1. **Materials**: Conductive polymers, carbon-based micro/nano materials, metallic nanoparticles/nanowires, and fiber-based electrodes are discussed for their unique properties and potential applications. 2. **Fabrication Technology**: Various methods such as screen printing, digital printing, dip-coating, and conductive nano-coating technologies are explored for their effectiveness in integrating electronic functions into fabrics. 3. **E-Components, Devices, and Applications**: The article details the development of fiber transistors, fabric antennas, electric connectors, and fiber-based circuitry, highlighting their performance under different mechanical deformations. 4. **Sensors and Sensing Networks**: Fiber-based sensors for strain, pressure, chemical, and optical sensing are reviewed, with a focus on their sensitivity, durability, and practical applications. The article concludes by emphasizing the potential of fiber-based wearable electronics in healthcare, environmental monitoring, displays, human-machine interaction, energy conversion, and communication systems, while also identifying areas for future research and development.The article provides a comprehensive review of fiber-based wearable electronics, focusing on materials, fabrication techniques, device structures, and applications. Fiber-based structures are highly desirable for wearable electronics due to their lightweight, long-lasting, flexible, and conformable properties. The advancement of nanotechnology has enabled the integration of electronic functions directly onto or inside single fibers, which are typically several to tens of microns thick. However, maintaining these functions during wear and deformation remains a significant challenge. The review covers the performance requirements of fiber-based wearable electronic products, emphasizing the correlation between materials, fiber/textile structures, and electronic and mechanical functionalities. It discusses the limitations of current materials and fabrication techniques, particularly in terms of manufacturability and practicality, and highlights the need for further scientific understanding to overcome these challenges. Key topics include: 1. **Materials**: Conductive polymers, carbon-based micro/nano materials, metallic nanoparticles/nanowires, and fiber-based electrodes are discussed for their unique properties and potential applications. 2. **Fabrication Technology**: Various methods such as screen printing, digital printing, dip-coating, and conductive nano-coating technologies are explored for their effectiveness in integrating electronic functions into fabrics. 3. **E-Components, Devices, and Applications**: The article details the development of fiber transistors, fabric antennas, electric connectors, and fiber-based circuitry, highlighting their performance under different mechanical deformations. 4. **Sensors and Sensing Networks**: Fiber-based sensors for strain, pressure, chemical, and optical sensing are reviewed, with a focus on their sensitivity, durability, and practical applications. The article concludes by emphasizing the potential of fiber-based wearable electronics in healthcare, environmental monitoring, displays, human-machine interaction, energy conversion, and communication systems, while also identifying areas for future research and development.