A 37-year-old woman has been charged over the death of plumber Rikki Colosimo, 35, in the small town of Humpty Doo on Sunday morning.

Northern Territory Police allege she struck Mr Colosimo, before driving back to where he lay and stopping for a ''period of time''.

Police say the car then sped off, accelerating quickly away from the scene.

''The 35-year-old man … is believed to have been lying on the roadway on Zamia Road when he was struck by a passing Mitsubishi Lancer,'' Detective acting Senior Sergeant John Worrall said.

The woman was in the car with three passengers, who have all been interviewed, police say.

The driver was arrested in Darwin and charged with hit-and-run causing death. She was bailed and will face court in January.

Police believe Mr Colosimo was either riding or walking his bicycle while making his way home from the party. The 35-year-old was from the ACT region, and had reportedly only been in Darwin for a few months.

His death has triggered an outpouring of emotion from families and friends on social media.

Mr Colosimo's younger sister Bobbie Murphy expressed her thanks to those mourning the loss on Facebook on Tuesday, but said her brother ought to be remembered for the ''amazing person'' he was. ''He wouldn't want us to be sad, but to celebrate his life and remember all of the great times you may have spent with him,'' she wrote.

''So, please smile, remember him for the truly amazing person that he was and learn the lesson that he taught us by living EVERY second of your life, because it can be so short.''

His sister-in-law, Kristina Calvert, described Rikki as the ''funnest and funniest person I've ever known''.

Police have seized the car alleged to be involved. Detectives and crash investigators have spoken with several people who were with Rikki before his death, but are still seeking information from anyone in the area at the time of the crash.