Simmons, 53, had endured a rocky time in the position and was suspended in September last year after criticising the board's selection policy for the West Indies' tour to Sri Lanka.
"In recent times, based on the public pronouncements of the coach and the approach internally, we have identified differences in culture and strategic approach," the West Indies Cricket Board (WICB) said in a statement.
"The WICB would therefore like to thank the coach for his contribution and wishes him the best in his future endeavours."
Former Test batsman Simmons was appointed as West Indies coach in March last year before being suspended six months later after complaining about interference with squad selection.
He returned to guide West Indies to their second World Twenty20 title in April when they beat England by four wickets in a sensational final in Kolkata, India.
With the departure of Simmons, Henderson Springer and Roddy Estwick will take charge of the West Indies team for their upcoming series against Pakistan in the United Arab Emirates. The team will be managed by Joel Garner.
Image: Phil Simmons
Photograph: Michael Steele/Getty Images
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