A spokesperson said that at around 6.25pm the 26-year-old victim was walking along Belfast’s Annadale Embankment when a male walked past him and stabbed him in the leg.
His injuries are not believed to be life threatening.
Police are appealing for information about the attacker – who is described as being approximately 6ft tall, with stocky build, dark stubble, wearing a black beanie hat with white writing on it, a black zip up jacket, jeans and trainers.
Inspector Gordon Wilkinson said: “I would appeal to anyone who may have witnessed this incident or who has any information to contact Police at Lisburn Road on the non-emergency number 101.
“Or, if someone would prefer to provide information without giving their details they can contact the independent charity Crimestoppers and speak to them anonymously on 0800 555 111.”