Geoffrey Mayne

{{Use dmy dates|date=July 2019}}

{{Infobox Bishop

| honorific-prefix =

| name = Most Reverend Geoffrey Mayne

| honorific-suffix = AM DD

| bishop_of = Bishop of the Australian Defence Force

| image = Mitre (plain).svg

| caption =

| province =

| diocese =

| see = Military Ordinariate of Australia

| enthroned = 27 February 1985

| ended = 15 July 2003

| predecessor = John Aloysius Morgan

| successor = Max Leroy Davis

| ordination = 21 July 1956

| consecration = 27 February 1985

| other_post = Titular Bishop of Mopta

| birth_name =

| birth_date = {{Birth date|1928|8|27|df=yes}}

| birth_place =

| death_date = {{death date and age|2003|9|14|1928|8|27|df=yes}}

| death_place = Canberra, ACT

| buried =

| nationality =

| religion = Roman Catholic

| residence =

| parents =

| spouse =

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| occupation =

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| alma_mater =

| signature =

}}

Geoffrey Mayne (27 August 1928 – 14 September 2003) was the Catholic Bishop of the Australian Defence Force from 27 February 1985 until 15 July 2003.