The assault happened on Park Street in Brighouse in the early hours of Sunday morning between 2.50am and 2.55 am.
The victim was on a night out with two female friends when he became involved in an altercation with a group of unknown men on Bethel Street, near to the Halifax Bank.
West Yorkshire Police say he was then chased and stabbed in the back, needing to be hospitalised as a result.
Any witnesses to the incident are asked to contact Det Con Alison Mitchell on 101 quoting crime reference 13180140622