Police have arrested a man after being called to Middleton Park Avenue at around 3.20pm this afternoon.
A West Yorkshire Police spokesman said: "Officers and emergency services attended to find one man who had suffered injuries which appeared to have been caused by a knife.
"A man was arrested nearby on suspicion of affray and is custody.
"The victim was taken to Leeds General Infirmary for treatment to a none life threatening head injury.
"Enquiries remain ongoing by Leeds CID."
Police said that it had been reported that two men had been fighting.
The street police were called to is next to Middleton Primary School.
The ages of the men are not currently known.