Traditional auditory impairment grading systems rely merely on hearing loss decibel values, focusing on functional outcomes while ignoring lesion anatomy, pathological mechanisms and injury reversibility. Such generalized criteria cause poor clinical adaptability and disjointed diagnosis and rehabilitation, failing to meet the demands of precision medicine and individualized rehabilitation. To address these limitations, this study proposes an innovative etiology-centered auditory impairment classification and grading system based on otological anatomy and auditory pathology. A four-category and four-level multidimensional evaluation framework is established to match diverse pathological hearing impairments with personalized clinical interventions. Furthermore, an integrated intelligent rehabilitation system is developed, including a novel jaw-oriented bone conduction device for non-invasive auditory compensation of reversible conductive impairment and a multilingual visual speech correction system for visual compensatory rehabilitation of irreversible hearing impairment. This study constructs a closed-loop system covering etiological classification, individualized intervention and intelligent rehabilitation. It effectively compensates for the deficiencies of traditional grading and rehabilitation modes, providing a novel theoretical framework and feasible technical solution for precise diagnosis and inclusive intelligent rehabilitation of global hearing impairment populations.