The present study explored the morpheme transposition process of two-character Chinese words in the upper and lower visual fields by adopting a dual-target rapid serial visual presentation paradigm. The results showed that the identification accuracy of canonical words was better in the lower visual field, whereas the accuracy of transposed words was almost identical in the upper and lower visual fields. Furthermore, there was no significant difference between canonical and transposed words at 0°, 2°, 4°, and 6° eccentricities in the upper visual field. However, the accuracy of canonical words was markedly higher than that of transposed words at 2°, 4°, and 6° eccentricities in the lower visual field. Finally, the character order errors mainly occurred at 0°eccentricity with a duration of 100 ms in vertical visual fields. These findings, taken together, indicated that the character transposition affected the lexical process of two-character Chinese words in the lower visual field but not in the upper visual field, and the character order of words was more likely to be reversed at 0° eccentricity and the initial stage of visual word processing in vertical reading.