Experiments and direct numerical simulations are employed to investigate the laminar separation bubble that forms on the suction side of a static and plunging wing section for a modified NACA 643 - 618 airfoil at a chord Reynolds number of Re = 200k. The simulations show that the transition process in the separated shear layer is mainly due to the amplification of Kelvin-Helmholtz instabilities, followed by shedding of strong spanwise coherent structures that lead to the reattachment of a turbulent boundary layer. A plunging motion with an amplitude of h = 6% of the chord and a reduced frequency of k = 0.67 is imposed to the wing in a wind tunnel experiment, at a nominal angle of attack of zero degrees. Surface pressure and 2D Particle Image Velocimetry measurements are used to track the unsteady evolution of the bubble along the plunging cycle and its effect on the wing’s loading. A hysteretic behaviour is observed for the bubble size and location during the cycle. No bubble bursting is observed at these conditions, thus having a small impact on the global lift and pitching moment coefficientsof the wing.