This study investigated how code-switching from Mandarin to English affected pitch range and pitch reset. Our intuition was that speakers tend to raise their pitch when producing English words embedded in Mandarin utterances. Utterances in Mandarin-only, English-only, and code-switched conditions were created to observe the acoustic distinctions. Two primary aspects were explored. First, we compared the pitch range values of keywords between the English-only and code-switched conditions. Second, we examined the manifestation of pitch reset patterns in keywords by comparing the Mandarin-only condition with the code-switched condition. The results show that in the keywords, the pitch range values in the code-switched condition significantly surpassed those in the English-only condition, suggesting a notable pitch difference in how the keywords were produced during code-switching. As for pitch reset, the values of keywords in the code-switched condition were significantly greater than those in the Mandarin-only condition, highlighting a discernible language transition (from Mandarin to English) in the code-switching process.