Forward swept wing is one of the forms of aircraft layout. Regarding the aerodynamic characteristics of induced drag of forward swept wings, existing papers have provided confusing understandings. In order to clarify the concept of induced drag of forward swept wings, this paper calculates and analyzes the induced drag characteristics of forward swept wings using nonlinear lift surface, lift line, and high-precision Euler equation solving methods, and compares them with corresponding aft-swept wings and straight wings. The research results indicate that there is a problem with the perception that the induced drag of forward swept wings is smaller than that of aft-swept wings. Even within the framework of potential flow theory, the induced drag of forward swept wings is greater than that of aft-swept wings. This paper also briefly summarizes the advantages of forward swept wings.