Emergency services were called to the bus station in Market Place, Pudsey, at 10.40pm on Friday, June 18.
The man was taken to hospital for emergency treatment and remains in a serious but stable condition.
West Yorkshire Police confirmed they had arrested a 17-year-old man on suspicion of wounding with intent. He remains in custody.
.Detective Inspector Andrew Lockwood, of Leeds District CID, said: “We are treating this incident very seriously and are carrying out extensive enquiries to establish the full circumstances.
“The victim is continuing to receive treatment in hospital, and we are monitoring his condition.
“We recognise that serious violence such as this will cause understandable concern in the community and we are working closely with our neighbourhood policing team colleagues who will be maintaining a visible presence in the area to reassure people.”
Anyone with information is asked to contact Leeds District CID via 101 quoting crime reference 13210306118.
Information can also be given anonymously to Crimestoppers on 0800 555 111.