The governing body said in a statement that analysis of Lawson's action -- reported as suspect in July -- showed that his arm was not flexed at the elbow by more than the 15 degrees allowed under current regulations.
The governing body also noted that Lawson's bowling action had improved since he was reported during a Test in Sri Lanka, although it added that there were still "areas of potential concern" which had been notified to the West Indies Cricket Board.
David Richardson, the ICC General Manager - Cricket, said: "The findings of the report mean that Jermaine can continue to bowl in international cricket.
"It is important to be aware, however, that no bowler is ever 'cleared' as they could simply revert to bad habits. All bowlers are subject to further reporting if the match officials are of the view that they have concerns about whether a delivery or deliveries conform to the laws of cricket when observed with the naked eye."
Lawson took eight wickets in the Test which led to him being reported, although that was not enough to prevent a second-string West Indies side slumping to a six-wicket defeat.
Umpires Simon Taufel of Australia and Nadeem Ghauri of Pakistan had expressed particular concern about the bowler's short-pitched deliveries.
Lawson was also reported after taking 7-78 against Australia in Antigua in 2003.
The latest study of the bowler's action was undertaken by biomechanics expert Dr Paul Hurrion, at the Sports Science Department of the University College, Chichester in England.