Online video chat is emerging as one of the common forms of computer-mediated communication (CMC). It can also be easily exploited by deceiver for persuasive conversation. Research on deception cues in CMC is gaining increasing attention in recent years but has largely ignored this new medium. This study aims to investigate the effect of eye movement behavior in the detection of deception in online video chatting. A laboratory experiment is conducted to test pupil dilation and blinking rate as possible cues to online deception. During the study, the eye movement behavior of participants was captured using an eye tracking system. The preliminary results confirmed the effect of pupil dilation but did not yield any significant effect for blinking rate.