Engineered cementitious composites (ECC) have good crack width control ability and self-healing potential, which can effectively improve the performance and durability of concrete structures and has been used in various environmental conditions. The healing ability of ECC varies under different environmental conditions, and currently there is relatively little research on the healing behavior of ECC in different environments. In order to study the effects of different environmental conditions on the self-healing behavior of ECC, three different environments including 0.5 mol/L NaCl solution, saturated Ca(OH)₂ solution, and natural environment were selected. Pre-cracked specimens were placed in each of the three environments, and the healing behavior and mechanism in different environments were explored through crack closure tests, strength recovery tests, electron microscopy scanning, and energy spectrum analysis. The experimental results show that the cracks in ECC under different healing environments have varying degrees of closure. As the healing cycle gradually increases, the degree of crack healing also gradually improves. NaCl solution and saturated Ca(OH)₂ solution have a positive effect on the crack healing. The ranking of the healing ability of ECC under different environments is obtained as follows: saturated Ca(OH)₂ solution > NaCl solution > natural environment. Healing materials in natural environment mainly include calcium-silicate-hydrate (C-S-H) gel and Ca(OH)₂. The healing material at the crack site in NaCl solution is mainly filled in the form of ettringite and Ca(OH)₂. In a saturated Ca(OH)₂ solution environment, a large amount of healing material is generated at the cracks, mainly in the form of CaCO₃ filling the crack.