Translation of scientific texts has been regarded as having the least freedom and variety in rendition; however, inconsistencies occur when translators work with two language systems that differ in reference to time, such as between Chinese and English. Tense is one of the core components of English grammar, but such information is not apparent in Chinese because the Chinese language tends to express time with lexical items in context instead of adding morphological changes to the verbs. The present study collected Chinese-English translated texts from graduate students on topics in the popular science domain. Analyses were conducted by comparing the tense information in the source text and the tense rendered in the target text on a sentence-by-sentence basis. The results showed that while the source text in Chinese stayed in the present tense, the students tended to switch from the present tense to the future or past tense during translation. In particular, the Chinese word "hui" has a habitual meaning that usually describes facts instead of presenting a future tense in scientific texts, but the students tended to interpret it as a future tense word, thus producing inappropriate tense shifts during translation. The pedagogical implication of such findings on inconsistent tenses between the source and target texts suggests that in the teaching of translation, analysis of the tense structure of the Chinese text and the consistency of tense information rendered in English should be emphasized.