Aircraft is the science of aerodynamics that is associated with fluid flow, which is related to performance in today's aviation. One of them is technological advances in the world of aviation, namely various developments and modifications of airfoils that are carried out to delay flow separation, one of which is with a vortex generator. The flow separation event in the frictional flow on the surface of the wing (boundary Layer) can cause a stall. Therefore, by delaying the separation, the drag will be small and will get an increase in the lift force. The research study is the characteristic of fluid flow that crosses a parabolic vortex generator with the oil flow visualization method. This study aims to visually observe the fluid flow characteristics on the upper surface crossing the NACA 43018 airfoil with varying positions of the vortex generator and angle of attack (AoA). The vortex generator profile is positioned x/c = 20% from the leading edge. By using variations of Reynolds Number (Re) and angle of attack (α) on the airfoil. The freestream speed used is 20 m/s, at angles of attack (α) = 0°, 4°, 10°, 12°, 15°, and 17°. It can be proven that this research with the addition of a parabolic vortex generator increases the aerodynamic performance of the airfoil, where the aircraft from AoA 0°to 12°proves that the increasing speed of the transition to the laminar boundary layer is concluded to be a turbulent boundary layer. Based on visual experiments using a parabolic vortex generator, it shows that there is a delay in flow separation on the upper surface of NACA 43018 at an angle of attack of α = 12°to 15°.