That Chinese text does not have a word boundary pose a question of whether L2 learners of Chinese are affected by the text at a word boundary. The present study consisted of two related experiments, i.e., one reaction time experiment and one pencil-paper experiment on the ambiguity of Chinese segmentation. The reaction time experiment was conducted by 2×2×2 within-subjects ANOVA (analysis of variance) with text presentation, length and difficulty of a sentence as the independent variables, and reading reaction time as the dependent variable. The results indicated that there were only significant main effects for word boundaries, length and difficulty of a sentence while the two/three-way interactions were not significant. Meanwhile, the pencil-paper experiment was conducted by single factor within-subjects ANOVA with the possible number of word combination (PNWC) as the independent variable, and the incorrect number of the ambiguity of Chinese segmentation which was made by the subjects as the dependent variable. The results demonstrated that there was a significant main effect for PNWC, without significant two-way interaction. Word boundary can help L2 learners of Chinese reading texts and understanding the meaning of texts fast. Apart from theoretic implications, this paper also tried to propose an approach on Chinese segmentation which can be used in Chinese as a foreign language classroom.