Kenneth Hine, 53, of Almondsbury Road, Paulsgrove, had picked up the drugs from Leeds and was on his way back to Portsmouth to carry on dealing.
But he was stopped near junction nine of the M3, for the A34, and officers found the stash inside two vacuum-sealed laundry bags.
Police from the South Eastern Regional Organised Crime Unit (Serocu) raided his home and found 4kg of cannabis, scales, deal lists and snap bags.
Woman, 44, whose large Dobermann dog mauled girl, 3, on Leigh Park street released back into neighbourhood by police
Plans for redevelopment of Knight and Lee in Southsea get the green light - and work will begin soon, vows developer That Group
WATCH: This is the moment a man with a grudge fire-bombed a family's garden in Leigh Park
Unidentified woman’s body found in water as Hampshire police investigate ‘unexplained’ death
'It was just sheer panic from everyone': 'Horrific' bedroom fire in Paulsgrove ripped across several house roofs with 'pouring' smoke being seen from the motorway
A judge jailed him for two years. He was handed three months to run alongside the sentence after he admitted having cocaine at a hearing in May.
Det Sgt David Bone, from Serocu’s investigations team, said: ‘Hine was stopped with a substantial amount of cannabis in his vehicle, which inevitably would have made its way on to the streets of Portsmouth.
‘We use a number of tactics to apprehend criminals, and continue to work relentlessly to ensure that the south east is a hostile environment for drug dealers to attempt to operate.
‘I would urge anyone who suspects that drug offences are being committed in their area to contact police on 101, or by phoning Crimestoppers, anonymously, on 0800 555 111.’