Bonosus of Trier was a 4th-century Catholic bishop who served the diocese of Trier. Following the exile of Bishop Paulinus in 353, Bonosus was chosen to succeed him, but he initially declined the position. He believed Paulinus remained the legitimate leader, an act of integrity that led to his imprisonment by Emperor Constantius II. He eventually accepted the episcopal role only after Paulinus had passed away. During his tenure, he was active in the theological struggle against Arianism.