Objective To obtain a latent, low-temperature and fast curing dicyandiamide agent. Methods A new latent curing agent of dicyandiamide modified by bisphenol A type phenolic aldehyde resin was synthesized and the structure was characterized by FTIR spectra. The impact of dicyandiamide dosage on product performance was investigated. The activity of the modified curing a- gent, the dosage and the curing temperature were studied with differential scanning calorimetry (DSC). Results The results showed that the suitable molar ratio of dicyandiamide and phenolic aldehyde was 0. 6 : 1, the optimal dosage of the modified curing agent was 30% (relative to the epoxy resin mass fraction), and the constant curing temperature after modification was 127 ℃. Conclu- sions The resulting curing agent of bisphenol A phenolic resin modified dicyandiamide exhibited the best comprehensive perform- ances.