Abstract. Under a warming climate, occurrences of wildfires have been increasingly more frequent in boreal and arctic forests during the last few decades. Wildfires can cause radical changes in the forest ecosystems and permafrost environment, such as irreversible degradation of permafrost, successions of boreal forests, rapid and massive losses of soil carbon stock, and increased periglacial geohazards. Since 2016, we have gradually and more systematically established a network for studying soil nutrients and monitoring the hydrothermal state of the active layer and near-surface permafrost in the northern Da Xing’anling (Hinggan) Mountains in Northeast China. The dataset of soil moisture content (0–9.4 m in depth), soil organic carbon (0–3.6 m), total nitrogen (0–3.6 m), and total phosphorus and potassium (0–3.6 m) have been obtained by field sampling and ensuing laboratory tests. Long-term datasets (2017–2022) of ground temperatures (0–20 m) and active layer thickness have been observed by thermistor cables permanently installed in boreholes. The present data can be used to simulate changes in permafrost features under a changing climate and wildfire disturbances and to explore the changing interactive mechanisms of the fire-permafrost-carbon system in the hemiboreal forest. Furthermore, can provide baseline data for studies and action plans to support the carbon neutralization initiative and assessment of ecological safety and management of the permafrost environment. This dataset can be easily accessed from the National Tibetan Plateau/Third Pole Environment Data Center (https://doi.org/10.11888/Cryos.tpdc.300933, Li and Jin, 2024).