Inzamam was found guilty of bringing the game into direpute for his team's failure to take the field after tea on the fourth day of the fourth Test against England at the Oval last month, causing the match to be forfeited.
The four match ban is not as severe as it could have been, with the maximum penalty being four Test matches or eight one-day matches.
Inzaman has 24 hours to appeal the charge, and if he chooses not to he will miss Pakistan's opening matches of the ICC Champions Trophy which begins in India on October 15.
The Pakistan captain was cleared of charges of ball tampering stemming from the same match.
Match referee Ranjan Madugalle ruled that although Inzamam had been found not guilty of ball tampering, the Pakistan skipper had been found guilty of a level three ICC rule and faced the four match ban.
"On the first charge of ball-tampered under paragraph 2.9 of the ICC Code of Conduct, I find Mr Ul-Haq not guilty," Madugalle said in a statement.
"Having regard to the seriousness of the allegation of ball-tampering - it is an allegation of cheating - I am not satisfied on the balance of probabilities that there is sufficiently cogent evidence the fielding team had changed the condition of the ball.
"In my judgment, the marks are as consistent with normal wear and tear of a match ball after 56 overs as they are with deliberate human interventions."
"Mr Ul-Haq has been found guilty of deliberately refusing to come on to the field on two occasions as a protest against the umpires, so interrupting play," the statement said.
"I decide that Mr Ul-Haq should be banned for four one-day international matches."
The fourth Test forfeit
The controversy started at the Oval on August 20, when umpires Darrell Hair and Billy Doctrove changed the ball and penalised the fielding Pakistanis five runs – in effect accusing them of altering the state of the ball.
Play continued until the tea interval, after which the Pakistan team refused to return to the field in protest over the ball tampering allegations.
This caused the umpires to rule the match a forfeit and awarded the win to England – the first time a match had been decided by officials in Test cricket's 129 year history.
The ICC's ruling that has found Inzamam and the Pakistanis not guilty of ball tampering will certainly put umpire Hair back in the spotlight as he was seen as the main official at the centre of the ball tampering allegations.
Hair is due to umpire at the Champions Trophy one-day tournament – a move that has been objected to by the Pakistan and Indian cricket boards.