Jack Masters

{{Short description|Canadian politician (1931–2024)}}

{{Use Canadian English|date=September 2021}}

{{Use dmy dates|date=January 2024}}

{{Infobox officeholder

| name = Jack Masters

| image =

| caption =

| order = 4th Mayor of Thunder Bay

| term_start = 1986

| term_end = 1991

| predecessor = Walter Assef

| successor = David Hamilton

| order2 = MP for Thunder Bay—Nipigon

| term_start2 = 1980

| term_end2 = 1984

| predecessor2 = Bob Andras

| successor2 = Ernie Epp

| birth_name=John Gerald Mastrangelo

| birth_date = {{birth date|df=y|1931|9|27}}

| birth_place = Fort William, Ontario, Canada

| death_date = {{death date and age|2024|1|5|1931|9|27|df=y}}

| death_place = Thunder Bay, Ontario, Canada

| constituency =

| party = Liberal

| spouse =

| profession =

| religion =

| signature =

| footnotes =

}}

John Gerald Masters (born John Gerald Mastrangelo, 27 September 1931 – 5 January 2024) was a Canadian politician. He served as mayor of the city of Thunder Bay, Ontario, and as a federal Member of Parliament.