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The temperature sensitivity of multiple carbon (C) pools in the soil plays an important role in the C cycle and potential feedback to climate change. The aim of this study was to investigate the temperature sensitivity of different biochars in soil to better understand the temperature sensitivity of different soil C pools. Biochars were prepared using sugarcane residue at temperatures of 300, 500 and 800 degrees C (representing different C pools) and C skeletons (representing the refractory C pool in biochar) were obtained from each biochar. The sugarcane residue, biochars and C skeletons were used as amendments in a simulated soil with microbes but without organic matter. The temperature sensitivity of the amended soils was characterised by their mineralisation rate changes in response to ambient temperatures. The temperature sensitivity of treatments with relatively refractory biochars was higher than that with labile biochars. The temperature sensitivity of treatments with biochars was lower than for their corresponding C skeletons. The different temperature sensitivity of treatments was attributable to the different internal C structures (i.e. the functional groups of C=C and aromatic structure) of amendments, determining the biodegradability of substrates. Dissolved organic matter and microbial enzyme activity of biochars were lower than those of corresponding C skeletons, and decreased with increasing pyrolysis temperature. The temperature sensitivities of treatments with biochars, C skeletons and sugarcane residue were negatively correlated with the properties of dissolved organic matter and microbial enzyme activities (especially dehydrogenase) in soil.