Objective: We reviewed the records of kidney biopsy in patients aged 65 and older from January 2009 to December 2019 at eight St. Mary hospitals affiliated with the Catholic Medical Center in Korea. We compared the treatment response of patients diagnosed with glomerulonephritis who were treated with conservative treatment and immunosuppressive treatment. Complete remission(CR) was defined as spot urine Protein/Creatinine ratio (P/C ratio)<0.3 and serum albumin >3.5 g/dL. Partial remission(PR) was defined as spot urine P/C ratio <0.3 and serum albumin >3.5 g/dL. Treatment failure(TF) was defined as creatinine level is twice that of diagnosis or starting renal replacement therapy. Methods: Of the 660 cases, a total of 442 cases were included in the analysis, excluding 133 cases of renal cell carcinoma, 83 cases of post kidney transplant status and 2 cases of tuberculosis. The mean patient age was 75.77. The mean creatinine is 1.86, the mean glomerular filtration rate is 54.17. The mean spot urine P/C ratio is 5.60. The most common histopathological finding is membranous nephropathy (86 patients; 19.5%) followed by IgA nephropathy (66 patients; 14.9%), focal segmental glomerulosclerosis (53 patients; 12.0%) and minimal change disease (36 patients; 8.1%). The group receiving immunosuppressant therapy has a high rate of not reaching TF. (Odd Ratio(OR) (95% CI) 1.734 (1.162-2.586), p value=0.007) The group receiving immunosuppressant therapy has a high mortality. (OR (95% CI) 1.830 (1.095-3.059), p value=0.02) but has a low rate of GFR reduction to less than 60% at the last follow up day, although not statistically significant. (OR (95% CI) 1.265 (0.815-1.963), p value= 0.295) Results: The use of immunosuppressive therapy in older patients with glomerulonephritis requires careful management. Conclusions: Objective: The number of elderly patients with glomerulonephritis diagnosed through kidney biopsy is increasing. However, few studies have been done on the usefulness of using immunosuppressive therapy in these patients. Methods: We reviewed the records of kidney biopsy in patients aged 65 and older from January 2009 to December 2019 at eight St. Mary hospitals affiliated with the Catholic Medical Center in Korea. We compared the treatment response of patients diagnosed with glomerulonephritis who were treated with conservative treatment and immunosuppressive treatment. Complete remission(CR) was defined as spot urine Protein/Creatinine ratio (P/C ratio)<0.3 and serum albumin >3.5 g/dL. Partial remission(PR) was defined as spot urine P/C ratio <0.3 and serum albumin >3.5 g/dL. Treatment failure(TF) was defined as creatinine level is twice that of diagnosis or starting renal replacement therapy. Results: Of the 660 cases, a total of 442 cases were included in the analysis, excluding 133 cases of renal cell carcinoma, 83 cases of post kidney transplant status and 2 cases of tuberculosis. The mean patient age was 75.77. The mean creatinine is 1.86, the mean glomerular filtration rate is 54.17. The mean spot urine P/C ratio is 5.60. The most common histopathological finding is membranous nephropathy (86 patients; 19.5%) followed by IgA nephropathy (66 patients; 14.9%), focal segmental glomerulosclerosis (53 patients; 12.0%) and minimal change disease (36 patients; 8.1%). The group receiving immunosuppressant therapy has a high rate of not reaching TF. (Odd Ratio(OR) (95% CI) 1.734 (1.162-2.586), p value=0.007) The group receiving immunosuppressant therapy has a high mortality. (OR (95% CI) 1.830 (1.095-3.059), p value=0.02) but has a low rate of GFR reduction to less than 60% at the last follow up day, although not statistically significant. (OR (95% CI) 1.265 (0.815-1.963), p value= 0.295) Conclusions: The use of immunosuppressive therapy in older patients with glomerulonephritis requires careful management.