Offshore floating residences offer a future sustainable solution for coastal cities with limited land availability. However, the premise of floating residences relies on safe and efficient construction, which presents significant challenges due to the significant difference from on-land construction. The complex environmental factors such as waves, wind, and humidity make offshore construction highly difficult. Construction activities are disrupted by these intricate environmental factors, resulting in more safety risks and uncertainties compared to on-land construction. Therefore, worker activities in offshore construction require extensive monitoring and tracking. Traditional worker positioning and tracking methods, such as various tag sensors, may be difficult to deploy effectively on offshore platforms. This study proposes a real-time worker tracking method in offshore construction scenarios using LiDAR scanning. LiDAR scans the entire construction site in a contactless manner and identifies and locates multiple workers without requiring them to carry any positioning devices. An algorithm for worker identification, positioning, and tracking is developed based on LiDAR scanning data. The proposed method has been validated through on-site experiments, with results showing a positioning accuracy of 0.05 m based on real-time LiDAR scanning. This research provides essential safety monitoring capabilities for offshore construction and can further enhance worker safety in complex construction scenarios.