Nan Triveni Achnas is an Indonesian film director.

Born in Singapore in 1963, she grew up in Kuala Lumpur, Malaysia. Achnas graduated from the Faculty of Film and Television at the Jakarta Institute of the Arts. She also completed a master's degree in Film Studies at the University of East Anglia in 1996 where she was a Chevening Scholar. While graduating from the University of East Anglia, she directed a film entitled The Only Day (1988) as her diploma film. It won the Grand Prix at the Asian Young Cinema Film Festival in Tokyo. In 2020, she obtained her PhD degree at Nanyang Technological University Singapore with a doctoral thesis on “Experimenting with the essay form and wayang in contemporary Indonesian filmmaking : when shadows are grey”. Apart from directing films, Achnas' teaches film at the Jakarta Institute of the Arts considered as the main film school in Indonesia.