Abstract: With the continuous enhancement of refinement for marine engineering projects in China, higher requirements have been imposed on the stability and autonomous controllability of high-precision positioning on the sea. It is, therefore, imperative to analyze the high-precision positioning performance of the BeiDou Navigation Satellite System (BDS) in marine environment. By using the data measured with Global Navigation Satellite System (GNSS) in the northern part of the South China Sea and applying the precise point positioning software PRIDE PPP-AR developed by Wuhan University, the Precise Point Positioning (PPP) experiments are conducted by means of single BDS, single Global Positioning System (GPS) and the full GNSS constellation, respectively, and the positioning results are compared and analyzed. The results indicate that in Haikou of Hainan the accuracy of static simulated kinematic PPP results can be comparable across the three modes of single BDS, single GPS, and the full GNSS constellation, of which the positioning results obtained with the full GNSS constellation have the highest accuracy, being better than 0.05 m in all three directions. In the northern South China Sea the geometric configuration observed with single BDS is superior to that with single GPS. Taking the PPP results from the full GNSS constellation as the reference, the PPP results from single BDS exhibit a high degree of agreement with those from the full GNSS constellation, with the Root Mean Square Errors (RMSEs) in horizontal and vertical directions being lower than 0.01 and 0.02 m respectively, significantly better than PPP results from single GPS. By taking the relative positioning results as the reference, the accuracy of the PPP results from single BDS is consistent with that from the full GNSS constellation, with an error being approximately 0.05 m lower than that of the PPP results from single GPS. Moreover, the kinematic PPP positioning results derived from single BDS data sampled at a sampling rate of 10 Hz or higher contain centimeter-level dynamic position signals, but not present in the positioning results obtained with a 1 Hz sampling rate. This indicates that the high-sampling-rate BDS data can effectively support deformation monitoring requirements in the kinematic marine environment.