J.W. McMillan may refer to:

• James W. McMillan (1825-1903), American soldier
• J.W. McMillan (brick manufacturer) (1850-1925), Scottish-American businessman

• Bishop of Aracatuba
• Bishop of Aracuai
• Bishop of Arassuai
• Bishop of Arassuaí
• Bishop of Arauca
• Bishop of Araçatuba
• Bishop of Araçuaí
• Bishop of Ardagh and Clonmacnois
• Bishop of Ardagh-Clonmacnois
• Bishop of Ardagh & Clonmacnois
• Bishop of Ardagh & Clonmacnoise
• Bishop of Ardagh-Clonmacnoise
• Bishop of Ardfert-Aghadoe
• Bishop of Ardfert & Aghadoe
• Bishop of Arecibo
• Bishop of Arequipa
• Bishop of Arezzo, Cortona and Sansepolcro
• Bishop of Arezzo, Cortona & Sansepolcro
• Bishop of Argentina
• Bishop of Argyll and the Isles (Episcopal)
• Bishop of Argyll and The Isles (Episcopalian)
• Bishop of Arichat
• Bishop of Arkansas
• Bishop of Aruba
• Bishop of Asmara