We were called at 5.44am on Sunday 10 March to a report of two vehicles colliding with a pedestrian on Woodside Avenue.
The pedestrian, a 23-year-old man from Chandlers Ford, was pronounced dead at the scene.
His next of kin has been informed.
The driver a black Vauxhall Astra and the driver of a blue Renault Megan are assisting officers with the investigation.
At this early stage of the investigation we are still trying to ascertain the exact circumstances of how the man died. As part of our enquiries we have arrested a 26-year-old man from Eastleigh on suspicion of murder.
Officers remain at the scene today to carry out enquires. The road was closed for some time but has since been reopened.
Anyone with information about this incident is asked to call 101 and quote 44190084129 or Operation Laminated.
In an emergency, call 999.