On March 5, 1878, at the age of sixty-nine, Octavius Winslow died suddenly at his residence in Brighton.

His obituary in the Brighton Gazette read:

We regret to have to announce the death of Dr. Octavius Winslow, the incumbent of Emmanuel Church. This melancholy event took place at the residence of Dr. Winslow early on Tuesday morning. Dr. Winslow had preached at his own church on Sunday, and his death was unexpected. Dr. Winslow was a man who well adorned his sacred office. His unaffected piety, burning eloquence, uprightness, and congenial, courteous, gracious character — caused him to be respected by all who came into contact with him, and loved by those who had closer opportunity of observing his sterling worth. His death will be mourned particularly by the large congregation who Sunday after Sunday were attracted to hear his masterly expositions and earnest exhortations. Generally his loss will also be felt by the Evangelical party in the Church, to whom his name was a tower of strength. He was a gentleman of a high-toned character — a laborious worker in his Master's service — of the most elevated piety; and, as his writings testify, deeply taught in the work of the Holy Spirit.