This survey was primarily undertaken to determine the kinds of flora which are prevalent in the middle ear of patients with chronic suppurative otitis media and also study the sensitivity of organisms thus isolated to antibiotics, as there is a paucity of literature on this subject. Chronic suppurative otitis media is one of the frequent disease in otolaryngologic field. In recent years, several authors made study of bacteriological examination of the discharge in chronic suppurative otitis media because of inadequate use of antibiotics for chronic suppurative otitis media. So, it is important to know periodically varieties of pathogenic organism and its sensitivity to give better treatment and minimize serious complications of chronic suppurative otitis media. Retrospectively, authors reviewed the bacteriological survey of 217 patients of chronic suppurative otitis media which visited in the Department of Otolaryngology, Ewha Womans University Hospital during the period of 6 years from January '72 to December '77 and also analyzed 220 strains and its sensitivity test to various antibiotics. The following results were obtained. 1) Variety of Pathogenic Organisms were numerous (220 strains), among which staphylococcus group was 48.6% (107) and pseudomonas group 24.4% (54), proteus group 6.8% (15), aerobacter group 3.2% (7), coliform bacillus group 2.5% (6) and streptococcus group 2.5% (5) and etc 12% in order of frequency. 2) In sex distribution, male patient(55.3%) were more than female patient (44.7%). 3) In age distribution, 11-20 years old (27.6%), 21-30 years old (26.8%) and 0-10 years old (23%) were most prevalent. 4) Duration of the disease, 0-5 years was dominant (58.5%). 5) The sensitivity to antibiotics, terramycin (80.9%), erythromycin (80%), sulfonamide (78.3%), penicillin (73.2%), streptomycin (62.7%), chloramphenicol (62.4%) were highly resistant, but geopen (100%), panimycin (100%), gentamicin (92.4%), cefalexin (76.2%), colistin (75%), minocin (67.9%) were highly sensitive. 6) Staphylococcus group were sensitive to panimycin (100%), geopen (100%), gentamicin (98.7%), cefalexin (90.6%), minocin (89.5%), lincocin (84.6%) and resistant to cloxacillin (100%), colistin (100%), sulfonamide (83.3%) and terramycin (83.3%). 7) Pseudomonas group were highly sensitive to panimycin (100%), geopen (100%) colistin (90.9%) and gentamycin (71.1%) and resistant to any other drugs. 8) Proteus group were sensitive to gentamicin (100%), minocin (100%), panimycin (100%), cefalexin (83.3%) and resistant to lincocin (100%), erythromycin (100%), streptomycin (73.3%) and penicillin (73.3%). 9) Aerobacter group were sensitive to terramycin (100%), minocin (100%), gentamicin (100%), kanamycin (85.7%) and resistant to erythromycin (100%), sulfonamide (100%), lincocin (100%) and penicillin (85.7%). 10) E. coli were sensitive to kanamycin (100%), gentamicin (100%) and panimycin (100%) and resistant to teramycin (100%), colistin (100%). 11) Streptococcus group were sensitive to gentamicin (100%) minocin (100%), panimycin (100%), kanamycin (85.7%) and resistant to penicillin (66.7%), chloramphenicol (42.9%) and erythromycin (42.9%).