Lithium extraction from lithium-bearing clay mineral (LiBC) has received significant attention due to the increasing demand of lithium for the advanced renewable energy industry. However, the low contents of valuable elements and stable physiochemical properties of LiBC result in high energy consumption and low efficiency in extracting lithium from LiBC. This study demonstrates a low-temperature strategy using (NH4)2SO4 as an additive to effectively extract lithium from LiBC. In details, the thermodynamic analysis verifies that Li, Al, and Fe can be converted to sulfates at 250–450 °C during thermal treatment, indicating the possibility for extraction of Li under low-temperature conditions. Subsequently, the leaching behavior of lithium under different roasting temperatures and water leaching conditions was investigated. The results show that 83.43 % of Li can be extracted under optimized conditions. The mechanism study was carried out through a number of characterization techniques including 3D microscope, TG-DSC, XRD, FTIR, and SEM. It reveals that formation of liquidus phase of molten salt is the key to achieve low-temperature roasting and transfer and reactions at the interface of molten salt and LiBC can be significantly enhanced that can easily breakdown the interlayer structures. Consequently, it offers distinct advantages, since the roasting temperature can be significantly decreased with minor impurity ions being leached into the solutions. This research therefore provides an efficient and environmentally friendly method for lithium extraction from minerals.