Purpose <p>Incorporating exogenous organic materials is a common agricultural practice to enhance soil organic C (SOC) accrual. Temperature changes could affect the contribution of organic materials to the soil C pool by affecting the decomposition of organic C. However, whether this process is affected by the C availability of organic materials remains to be explored.</p> Materials and methods <p>We conducted a 90-d experimental incubation by adding ¹³C labelled glucose, straw and biochar (characterizing exogenous materials with high, medium and low C availabilities) into soil at 10&#xa0;°C and 20&#xa0;°C, which aimed to explore the temperature sensitivities of exogenous and native C decomposition (Q₁₀) in soil with organic materials.</p> Results <p>It was found that warming led to a 16.4%, 33.3%, and 103.5% increase in the cumulative mineralization of exogenous C, respectively, with decreasing C availability levels of the organic materials. And the cumulative mineralization of native C increased by 22.7%, 19.8%, and 31.5%, respectively. Both the exogenous and native C pools exhibited higher Q₁₀ values when applying organic materials with limited available C. With the addition of organic materials with different C availabilities, the microbial community showed distinct assimilation and metabolism of exogenous and native C. High-availability materials promoted microbial C assimilation and metabolism, while low-availability materials enhanced microbial C use efficiency (CUE). Additionally, low-availability materials had higher activation energy (E_a).</p> Conclusion <p>Overall, increased C availability in organic materials reduced the Q₁₀ of both exogenous and native C pool, which could effectively mitigate warming-induced C loss.</p> Graphical abstract <p></p>