The stuffy and blocked feeling in the left ear may be caused by cerumen impaction, sudden deafness and secretory otitis media. 1. Cerumen impaction: When there is cerumen blockage in the left ear canal and it is more serious, it is easy to have symptoms such as ear stuffiness and hearing loss, i.e. the left ear will have a stuffy and blocked feeling. 2. Sudden deafness: this disease often occurs in times of stress, overwork, emotional excitement, etc., and patients often have symptoms such as tinnitus, hearing loss, stuffy ears and abnormal sensations around the ears. 3. Secretory otitis media: This disease can be caused by the obstruction of the eustachian tube, which will lead to the accumulation of fluid in the middle ear. It is usually accompanied by symptoms such as tinnitus, deafness and a stuffy feeling in the ear, so the left ear has a stuffy and blocked feeling. When there is a stuffy and blocked feeling in the left ear, it is recommended to go to the hospital in time for a clear diagnosis and receive professional treatment from the doctor.