To fully evaluate the usability of a raw Ca-bentonite source and to deeply understand the property of bentonite mineral are critical for applications of these special layered materials. Due to sodium bentonites have several advantages over calcium bentonites, especially in expansibility, cation exchange capacity, cohesive force, dispersibility, and thermostability, sodium-modification of Ca-bentonite is regarded as a top priority of effective utilization of abundant Ca-bentonite source in China. In present work, the purified Na-montmorillonite was synthesized by purification and sodium-modification of a raw Ca-bentonite source (Liaoning, China) by tri-roller grinder. Important influencing factor rolling times in purification and sodium modification process was investigated. Mineral compositions, microscopic morphology, and thermal stability were characterized by using different techniques. The crystalline phases and compositions were identified by X-ray powder diffraction (XRD). The morphology and structure were evaluated by scanning electron microscopy (SEM). The thermal properties were investigated using differential thermal gravity analysis (DTG) and differential thermal analysis (DTA) analysis.