The drilling project of gold deposit in the northern sea area of Sanshan Islands began in 2012 to the end of 2012. 138 holes were constructed in land and sea with the total workload of more than 150 thousand meters and contract amount of 240 million yuan. This project belongs to a mega construction project with the characteristics of long construction period, large workload, large amount of investment, large number of construction machines and difficult management. Because of its involvement of offshore drilling, construction environment, transportation, and the means of implementation are much different than land drilling, based on the offshore drilling practice, starting from the organization setting, the analysis is focused on the project safety, schedule, quality and cost management; each job responsibility is identified and important processes and key links are strictly controlled. A set of safe, scientific and effective management method suitable for offshore drilling construction is put forward, which can provide reference for similar offshore drilling project.