【Objective】 The accumulation rate of soil organic matter directly restricts the improvement of productivity of Pinus massoniana (Masson pine) in the process of vegetation restoration in eroded red soil area. The way to solve this problem has been an inevitable development process of Masson pine in eroded red soil area. Heterotrophic respiration, an important part of soil carbon emission, is a key factor affecting soil organic carbon accumulation. Therefore, it is of great significance to study the effects of Masson pine plantation restoration on heterotrophic respiration and its temperature sensitivity in eroded red soil areas. This will enhance our understanding of the carbon output process and effectively increase soil organic matter accumulation in eroded red soil areas. 【Method】 In this study, Masson pine plantations with different restoration years (Y0, Y14, Y31) were selected as the research objects. The effects of vegetation restoration on soil heterotrophic respiration were studied by separating and measuring different respiration components and combining with soil factors such as soil organic carbon, total nitrogen, soil temperature, water content and litter. The structural equation model of heterotrophic respiration between litter, soil temperature, soil nutrients, soil microorganisms and heterotrophic respiration were established to analyze the correlation between heterotrophic respiration and environmental factors in the process of vegetation restoration, and to explore the main factors affecting heterotrophic respiration. 【Result】 The results showed that the heterotrophic respiration (R_H) of the pine forests with different recovery years differed significantly. The R_H in site Y31 was significantly higher than that in site Y14 and Y0. The R_H in site Y0 was only 0.99 μmol·m^–2·s^–1, while in sites Y14 and Y31 it was 2.20 and 2.80 μmol·m^–2·s^–1, respectively. Temperature was the main influencing factor of the seasonal variation of heterotrophic respiration, explaining 40.6%(Y0), 62.2%(Y14) and 66.6%(Y31) of the seasonal variation, respectively. During the restoration process, the temperature sensitivity(Q₁₀)of relative humidity increased significantly, which was 1.58, 1.93 and 1.82, respectively. The relative contributions of R_H to total soil respiration in different recovery years are 77.94%(Y0), 70.84%(Y14), and 77.35%(Y31). The structural equation model showed that soil organic carbon (SOC), temperature and soil microbial diversity were the main factors affecting soil R_H during the restoration of Masson pine. SOC and soil microbial abundance significantly correlated with R_H, and soil temperature varied with vegetation restoration which significantly and negatively correlated with R_H. 【Conclusion】 The results of this study indicate that the accumulation of SOC and lack of effective physical protection during Masson pine vegetation restoration increase the decomposition of SOC by microorganisms; On the other hand, the reduction of soil environmental temperature, a continuous increase of bacteria and fungi abundance, and an increase of Proteobacteria, Ascomycota and Acidobacteria in the community further aggravate the microbes to the original strength of soil organic matter decomposition. Consequently, the continuous increase of heterotrophic respiration related carbon emissions limits the improvement of carbon sequestration efficiency of Masson pine forests. Therefore, the strong soil heterotrophic respiration in the eroded and degraded red soil area may be the key factor limiting further improvement of soil organic matter.