Marjan Janus

{{Short description|Dutch swimmer (born 1952)}}

{{Infobox sportsperson

|image=Marjan Janus 1966.jpg

| image_size =

|caption= Marjan Janus in 1966

|birth_date={{birth date and age|1952|01|31|df=y}}

|birth_place=Heemstede, Netherlands

| height = {{convert|1.65|m|ftin|abbr=on}}

| weight = {{convert|60|kg|lb|abbr=on}}

|sport=Swimming

|club=Heemsteedse Zwem- en Poloclub (HPC)

}}

Maria Alida Catharina "Marjan" Janus (born 31 January 1952) is a former breaststroke swimmer from the Netherlands. In 1968, she won the 100 m breaststroke event at the national championships, beating the long-time favorite Klenie Bimolt. She was therefore selected for the 1968 Summer Olympics, but failed to reach the final.