This paper describes the duration compensation phenomenon in Mandarin Chinese, which means that, for two segmental units, either phonemes or syllables, their duration compensates each other with regard to different unit types. As Mandarin Chinese is such a complexity, it is impossible to find invariable rules in it. However, we observed that the general trend of compensating remains. In this paper, we investigate how durations of within syllable and between syllable segments compensate. We also enter into details about how different phoneme types, tone types and location in sentences effect on the extent of compensation, and give our analysis from the points of phonetics and phonology.