Abstract: As an important member of non-precious metal materials, cobalt-based materials have been widely used in electrochemical energy storage and conversion fields such as supercapacitors and electrocatalysis due to their high theoretical capacity, good catalytic activity, and excellent thermal/chemical stability. However, cobalt-based materials have also many shortcomings, such as low conductivity, insufficient exposure of active sites, easy agglomeration and decomposition of active components during testing, poor structural stability, etc. In recent years, many studies have reported the modification of cobalt-based materials to improve their electrochemical performance. Based on this, this review introduces the modification research of cobalt-based materials in recent years in detail, mainly including morphology control, elemental doping, heterostructure construction, defect engineering and composite with specific supports materials, etc. Then, their electrochemistry applications including supercapacitors (SCs), electrocatalytic oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is systematically summarized. Finally, the current problems and future development directions of cobalt-based materials are proposed.