The 35-year-old was hit by a blue Volkswagen Polo on the A3M near Clanfield, late on Sunday night.
Paramedics rushed to his aid but he was later pronounced dead.
News of the death spread around the village yesterday morning, with residents and shoppers concerned the man had been in the road.
Sophie Brenton, manager at The Salon in Green Lane, lives in the road and saw traffic being re-directed.
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She said: ‘I was in bed and I heard all the traffic. I guessed it was an accident because of the amount.
‘There’s a crossing there but I wouldn’t want to cross there. It’s very tragic.’
Tia Miles, 18, a hairdresser at The Salon, added: ‘The traffic went all the way up to Waterlooville.
‘I can’t believe that, I’ve had no idea, it’s crazy.’
Hampshire police said the crash happened at 11.30pm on Sunday on the northbound carriageway of the A3M, close to junction 1.
The man, who has not been named, suffered serious injuries but later died.
In the village yesterday shoppers reacted with shock and upset.
One woman, 59, who asked not to be named, said: ‘It’s pretty horrendous.
‘It’s just sad. It’s very sad for the family, and the gentleman himself.’
A man, 55, who was working in the village centre yesterday added: ‘It’s always tragic when someone is killed unnecessarily like that, it’s dreadful.’
Nigel Padbury, 53, of Port Solent, was in the village shopping.
He said: ‘It’s unpleasant, I’m wondering why he was on the A3M, it’s a busy road.’
Hampshire police shut the road for three and a half hours, reopening it at around 4am yesterday morning.
Now investigators are piecing together what happened but are calling on any potential witnesses to come forward.
A Hampshire police spokeswoman said: ‘Officers from the Road Policing Unit are investigating the exact circumstances of this incident and would like to hear from any witnesses who saw what happened.
‘The driver of the VW Polo was uninjured and is helping officers with their enquiries.’
Call acting sergeant Melanie Adcock on 101, quoting Operation Windy.
Alternatively, call the crime-fighting charity Crimestoppers anonymously on 0800 555 111.