Cerumen impaction is quite common, and may be caused by deformity or by obstruction of the external auditory canal (EAC). A 38-year-old female presented with left earache and hearing block that had lasted a month. Severe cerumen impaction of the EAC was identified at a private clinic. Over the next month, five local treatment sessions were performed at our hospital, and the cerumen was gradually removed; finally, an expanded EAC was identified. Computed tomography revealed that the EAC had expanded into the mastoid process. Finally, keratosis obturan was diagnosed. This is rare and a curiosity, therefore we are reporting the case here.