The accurate estimation of the berthing state is fundamental for ships’ autonomous navigation during berthing processes. However, most existing methods only provide partial perception information, falling short of automatic berthing requirements. To address this issue, this paper presents a berthing state estimation pipeline that only relies on a 3D LiDAR, which can provide multiple types of berthing status information. The method employs the scan-matching algorithm to estimate the ship’s position and attitude. Additionally, the point cloud line-fitting algorithm is used to establish the berth line equation. By integrating the fitted berth line equation with ship motion data, the ship’s berthing state information is calculated. Experimental results demonstrate that, compared to existing methods, the method boasts significantly smaller errors and can provide more accurate and abundant berthing state information. The proposed method is effective and practical for automatic berthing state estimation and further provides key foundations for achieving automatic berthing operations.