Light, as an important environmental factor, has a crucial influence on the life activities of fungi. Botrytis cinerea is a typical light-responsive filamentous fungus capable of coordinating its growth and development with ambient light signals. Here, we find that Bcmads1, a key transcription factor in the light signaling pathway, can regulate the accumulation of many metabolites in a light-dependent manner, and demonstrate that N-vanillylnonanamide plays an important role in Bcmads1-regulated photomorphogenesis. Then, we confirm that Bcmads1 can directly regulate the expression of BcAMT1, which further affects the photomorphogenesis of B. cinerea by catalyzing the reaction from vanillin to vanillylamine in the N-vanillylnonanamide synthesis pathway. We find a new pathway of light signal transduction in B. cinerea and elucidate the new mechanism of Bcmads1 regulating N-vanillylnonanamide synthesis involved in the photomorphogenesis of B. cinerea.