Abstract: With the rapid development of the new energy vehicle and energy storage battery industries, the global demand for lithium resources continues to climb sharply, as lithium is an essential key raw material for manufacturing high−performance batteries. Clay−type lithium ore, which boasts enormous reserves and remarkable development potential, has become one of the important alternative directions for lithium resources in China, effectively alleviating the contradiction between the increasing demand for lithium and the shortage of traditional lithium ore resources. In this study, flotation concentrate from a certain clay−type lithium ore was selected as the research object, and lithium extraction experiments were carried out by adopting the suspension roasting–sulfuric acid leaching process. A series of single−factor and orthogonal experiments were conducted to systematically optimize the key process parameters of roasting and leaching, including roasting temperature, roasting time, air flow rate, leaching temperature, sulfuric acid concentration, liquid−solid ratio and leaching time. Meanwhile, characterization methods such as X−ray diffraction (XRD) and time−of−flight secondary ion mass spectrometry (TOF−SIMS) were employed to deeply reveal the lithium extraction mechanism of suspension roasting activated leaching. The experimental results show that under the optimal process conditions (roasting temperature of 600 ℃, roasting time of 30 min, air flow rate of 700 mL/min, leaching temperature of 80 ℃, sulfuric acid concentration of 20%, liquid−solid ratio of 4∶1 (mL∶g), and leaching time of 90 min), the lithium leaching efficiency can reach 90.42%. Mechanism analysis shows that before roasting, lithium mainly exists in a structural state within the dense aluminosilicate lattice of lithium−bearing chlorite, constrained by strong covalent Si–O and Al–O bonds as well as interlayer structures. The activity of Li⁺ is extremely low, making it difficult for H⁺ in sulfuric acid to penetrate the mineral framework and displace Li⁺ in the lattice during leaching, thus resulting in poor lithium leaching efficiency.In contrast, after suspension roasting, the crystal lattice of lithium−bearing chlorite undergoes distortion and amorphization, accompanied by weakened interlayer forces and enlarged interlayer spacing, which provide sufficient diffusion pathways for Li⁺ migration. A large amount of structurally bound lithium originally tightly confined in the lattice is converted into highly active free and weakly bound states, significantly enhancing the reactivity of Li⁺ and the driving force for ion exchange. Consequently, lithium is more readily displaced by H⁺ during acid leaching, achieving efficient lithium extraction and greatly improving the leaching performance.