Abstract: This study investigates a novel low-temperature roasting and non-acid leaching lithium extraction process using a new roasting aid,ASH,for an extremely low-grade clay lithium ore in Yunnan,China,with a lithium content of 0. 147%. The reaction mechanism was elucidated through X-ray Diffraction (XRD),Scanning Electron Microscopy with Energy Dispersive Xray Spectroscopy (SEM-EDS),and other analysis methods. Experimental results demonstrated that under the conditions of a sample to ASH mass ratio of 1∶0. 3,roasting temperature at 400 ℃,roasting time of 1. 0 hour,deionized water as the leaching agent,leaching time of 2 hours,leaching temperature of 70 ℃,and liquid-solid ratio of 5 mL/ g,the lithium leaching rate reached 83. 81%. Mechanism analysis indicated that while the main mineral phases in the sample remained unchanged before and after roasting-leaching,the intensity of diffraction peaks decreased. Post roasting-leaching,the sample surface exhibited uniform distribution of cracks and voids,along with decreased contents of Al,Si,Fe and Ti. This suggests a reaction between ASH and minerals,disrupting the mineral surface structure and generating soluble Li-ASH leachate. Compared to traditional roasting-leaching processes,this study′s lithium extraction process features lower roasting temperatures and acid-free leaching, reducing production energy consumption,simplifying the process flow,and offering significant insights for the green and efficient development and utilization of similar low-grade clay lithium ores.