Purpose. Vergence eye movements (EM) have been reported to be induced by radial optic flow (OF) (Busettini et al 1997, Yang et al 1999). However, it has also been reported that OF elicits versional optokinetic nystagmus (OKN) (Lappe et al 1998). We designed and used a simple OF that simulates natural viewing conditions to evoke a new type of OKN containing both version and vergence components. Methods. OF were generated on a PC monitor controlled with VEX-REX (LSR/NEI/NIH). The size of the stimuli was 30X30cm and viewing distance to its center was 30cm. Self-movements of a forward/backward translating observer over a textured horizontal plane were simulated. The subject seated still and EM responses to the OF were recorded with an infrared eye tracking system and analyzed off-line. Results. EMs had an OKN pattern characterized by an ocular following slow phase and a corrective quick phase. Version and vergence components were showed by extracting horizontal and vertical EM components in each eye. The slow phase and quick phase of vergence and version were analyzed for velocity and amplitude. Conclusion. Robust version and vergence EMs which are part of a novel OKN response can be induced by OF stimuli. The OKN of this type provides a new approach to study the interaction of the vergence and version. These reflexive vergence associated with OKN may be used to study development of the oculomotor system and objective evaluation of binocular function in children.