The water scooping system is the main part of the extinguishing aircraft system for realizing the water scooping function. Improving the design of water scooping system can shorten the time of water scooping and improve fire extinguishing efficiency as soon as possible. In this paper，CFD-based simulation analysis is performed on the original water scooping system of a certain type of amphibious aircraft.The results show that the unreasonable position of the outlets of the original water scooping system makes the volume flow difference between the two outlets are too large，and the water scooping time is to long, which is not conform to the water scooping requirements.In order to reduce the scooping time, two structural forms of water scooping system at different outlet positions are designed,and obtain the outlet position model with small volume flow difference by simulation analysis,and design the battle model with three different position base on the outlet model with small volume flow difference.when the baffle is 10mm from the center line of the water scooping pipe, the flow rate of the two outlets is roughly the same，and the water scooping time is 50% shorter than that of the original configuration of water scooping system, which is great significance to the subsequent design of the water scooping pipeline of amphibious aircraft.