More than 400 port workers were unhappy about wages and have accused the management of failing to pay them for overtime hours as required by labor laws, reported the South China Morning Post.
Crane operators and truck drivers at the Chiwan Container Terminal in Shenzhen, currently one of the world's busiest ports, stopped working at midnight on Tuesday.
According to an unnamed worker, industrial action was taken on International Labour Day to express their anger, reported the Post.
It is still unclear whether the strike action has ended, with port officials unable to provide any more information other than saying that services had partially resumed yesterday.
Calls to the company's headquarters and the local government have gone unanswered due to the week-long labor holiday in China.
Chiwan Container Terminal handled 5 million twenty-foot equivalent units (TEUs) in 2006, about a quarter of the total throughput at Shenzhen, currently the world's 4th busiest container port.