Objective To investigate the effect of simplified and traditional Chinese characters on near work-induced transient myopia (NITM) and its subsequent decay in myopes and emmetropes.Methods In an experimental study,young adult subjects (18-28 years) were classified into two groups based on their refractive errors: emmetropes (n=18) and myopes (n=18).Two sizes (12 pt,8 pt) and two types (simplified and traditional Chinese characters) were used to provide four different reading targets on the computer screen.Targets were presented in random order at 40 cm (2.5 demand)and the text was read for comprehension for 5 min.For()each target,NITM and its decay were measured using the free space Grand-Seiko WAM-5500 autorefractor.Results When data for all subjects were pooled,there was a significant effect on NITM from the type of character.For myopic subjects,NITM was larger for traditional Chinese characters (traditional Chinese characters: 0.61±0.34 D vs simplified Chinese characters: 0.53±0.33 D,t=2.298,P＜0.05).However,there was no effect for emmetropic subjects (t=0.789,P＞0.05).There was a significant difference between emmetropic and myopic subjects in the magnitude of NITM for traditional Chinese characters; myopes had a larger NITM than emmetropes (NITM myopes: 0.61±0.34 D vs emmetropes: 0.42±0.25 D,t=2.556,P＜0.05).There were differences in the decay time of NITM between the two refractive groups for all targets (decay time for myopes: 15.88±19.53 seconds vs emmetropes: 9.04±12.62 seconds,t=2.555,P＜0.05).Conclusion The results of the present study show that traditional Chinese characters had a more significant effect on myopic subjects than simplified Chinese characters; myopes were more susceptible than emmetropes to traditional Chinese characters.We suggest traditional Chinese characters are an environmental factor that affects the incidence of myopia in different areas.