The attempted theft occurred on Friday in Orniscourt when a man got into the vehicle and attempted to drive it away.
The driver managed to prevent his vehicle being taken however and it was crashed a short distance away.
Detective Inspector Allison Sweeting of Humberside Police said: “I want to remind all delivery drivers not to leave the keys in their vehicles – even for a moment. Opportunist thieves won’t think twice and will steal and potentially use it to commit further crime.
“It is a busy time of year for delivery drivers and so want to try and avoid not only the crime but of the driver potentially losing their livelihood.”