Due to the advantages of low cost,simple operation,convenient layout and stable performance,the pressure tide gauge has obvious advantages in depth measurement.Based on the actual situation of the project of the re-survey of crude oil wharf and navigable waters of China-Myanmar crude oil pipeline,the main factors affecting the data error of pressure tide gauge are analyzed in three aspects:atmospheric pressure,water density and zero drift.The following conclusions are drawn:synchronous observation of atmospheric pressure changes can eliminate or reduce the impact of atmospheric pressure changes;reducing the depth of the tide gauge and calculating the tidal data by using the bottom seawater density can significantly reduce the influence of the change of seawater density;by comparing the atmospheric pressure values observed synchronously by several tide gauges in the air at the same time,the correction value of zero drift can be determined.Combining with the actual situation of the project,the elevation transfer of synchronous tide gauge method is briefly introduced.