Display omitted •Working principle of supercapacitors (SCs) is introduced.•Recent advances on electrode materials for flexible SCs are reviewed.•Various ways to enhance the performance of flexible SCs are discussed.•Current challenges and future prospect of flexible SCs are suggested. In recent years, with the rapid economic development, real-time monitoring of human health has received extensive attention. Wearable health monitoring equipment with good malleability and resistance to distortion makes great progress. The flexible supercapacitors integrated into the textile are characterized by a simple production process, low cost, fast charge,-discharge speed, and long cycle life. Therefore it has superior performance and broad research prospects. This review mainly introduces the recent advances and challenges of flexible supercapacitors, focusing on various flexible substrates' synthesis and performance. It summarizes the most representative flexible electrode materials at this stage. The future development trend and direction of flexible supercapacitors are discussed as well. Finally, the challenges in practical applications are considered.