After the impoundment and navigation of the Three Gorges reservoir, the volume of freight traffic passing through the Three Gorges dam area continues to grow, and the ability is tending saturated. Moreover, the vessels are getting to a tendency of great size and large tonnage, and nearly 50% of the passing ships’ draught exceeds the designed standard. So it is an important matter to excavate under the kneel clearance to raise the passing ships’ draught and boost the volume of the passing ships are the today’s important problems. Combining the theoretical research with the on-board measurements, we carry out a systemic research on the running of the Three Gorges vessels, computing methods of the control standards about the volume and ship draught, on-board measurements of ships passing the lock and the control standards of the sea gauge, and have achieved several innovative achievements.