The state Supreme Court said Wednesday that the environmental group and neighborhood associations who sued over the plans did not have legal standing to challenge the proposal.
Groups including the Preservation Society of Charleston and South Carolina Coastal Conservation League sued two years ago, saying downtown residents are subjected to nuisances including air pollution and traffic congestion.
There have been seasonal cruises from Charleston in years past. Things changed three years ago when Carnival permanently based its 2,000-passenger liner Fantasy in the city, creating a year-round cruise industry.
Challenges to the plans are still pending in other courts.