San Francisco's Planning Commission voted 4-3 on Thursday, split along commissioners appointed by the mayor and those appointed by the city's Board of Supervisors.
It will be next considered by the supervisors.
The plan includes 8,000 residential units and a 450-foot high-rise on the island located in San Francisco Bay between the city and Oakland.
Critics say the man-made island would not fare well in an earthquake and that the project would increase traffic on the San Francisco-Oakland Bay Bridge.
Supporters say developing these 400 acres in the middle of San Francisco Bay is a unique opportunity.