Abstract: Abstract: Airfoil, as a product of aviation technology, has been widely used in the design of fluid machinery products. The aerodynamic characteristics of airfoils are a key factor in determining the performance of fluid machinery. When the existing airfoils are not able to meet the engineering requirements, it is necessary to redesign or trim the original airfoils. In this research, 2 ellipse arcs were used to form the mean camber line of the airfoil, and the corresponding equation was deduced. This equation controls the shape of the mean camber line by changing the maximum camber and the relative position of maximum camber, and adjusts the local shape by changing the 2 shape factors of the mean camber line. The mean camber line constructed by this method is smooth and continuous, and there is no knee point. Then the thickness distribution of the existing airfoil was superposed with the distribution function of mean camber line, and a thickness scale factor was introduced to adjust the thickness distribution. Ultimately, the design method for a series of airfoils based on mean camber line of double ellipse arcs is achieved, which is called DEA (double ellipse arcs) airfoil. The airfoil profile function constructed by this method has definite physical meaning, simple and reliable, and it is easy to realize serialization. In order to study the influence of airfoil characteristic parameters on aerodynamic performance of the DEA airfoil, the Clark-Y airfoil was taken as the basic airfoil, and a number of DEA airfoils were designed using the thickness distribution of the Clark-Y airfoil. Then the aerodynamic characteristics of the designed airfoils were solved by the X-foil software to study the influence of the maximum camber, the relative position of the maximum camber, the maximum thickness and the shape factors of the mean camber line on the DEA airfoil aerodynamic performance. There are 5 characteristic parameters in all that influence the shape of the DEA airfoil. We selected one of the 5 characteristic parameters as variable and fixed the other 4 characteristic parameters to design different DEA airfoils. And the aerodynamic characteristics were achieved at Reynolds number of 1.0×105. The calculation results of the 4 DEA airfoils with different values of maximum camber show that the increase of the maximum camber can improve the lift coefficient and ameliorate the characteristics of the lift-drag ratio. The calculation results of the 4 DEA airfoils with different values of relative position of the maximum camber show that as the relative position of the maximum camber moves forward, the lift coefficient under small angles of attack is improved, and the range of efficient lift-drag ratio gets broadened. The calculation results of the 4 DEA airfoils with different values of maximum thickness show that the increase of the maximum thickness can increase the maximum lift coefficient and the stall angle. At the same time, with the increase of thickness, the range of efficient lift-drag ratio also gets broadened. The calculation results of the DEA airfoils with different shape factors of the mean camber line also were achieved. At small attack angle, the change of the leading shape factors of the mean camber line has little influence on lift coefficient. With the decrease of the leading shape factors of the mean camber line, the interval of efficient lift-drag ratio has a tendency to move to high attack angle range. With the decrease of the trailing shape factors of the mean camber line, the lift coefficient and lift-drag ratio decrease gradually. Moreover, the interval of efficient lift-drag ratio also decreases and the decrease is mainly at the range of small attack angle. According to the adjustment principle of the above parameters, a new airfoil can be designed or modified to meet the needs of the target task.