The flow field of a neutrally buoyant turbulent round jet discharged horizontally into a wavy environment was investigated. A set of experiments applying the laser induced fluorescence technique was conducted to measure the free surface elevation and jet centerline movement simultaneously. The measurements show significant dynamic changes on jet centerline position and oscillation due to wave motion. The pattern of jet oscillation due to waves was classified into three categories: symmetric, asymmetric, and discontinuous motions. A simple prediction model was derived to calculate the jet oscillation under standing waves.