Objectives: This research aims to determine the prevalence of each primary glomerular disease (PGD), to examine the outcome of each PGD two years after the kidney biopsy, to examine if there are any differences in the outcomes of patients of different gender, age, body mass index and comorbidities, to examine which PGD caused kidney function to deteriorate the most two years after the biopsy, to examine if there is a correlation between the pathohistological diagnosis of PGD and the stage of chronic kidney disease at the time of biopsy and two years after it. Study Design: Cross-sectional study. Participants and Methods: The study involved 36 patients with a pathohistological diagnosis of PGD who had been monitored at the Department of Nephrology at the University Hospital Centre Osijek and underwent biopsy between February 2018 and the end of January 2019. Patients with kidney transplant were excluded from this study. Demographic and clinical data were collected from medical history – age, gender, height, body mass, PGD, comorbidities, biopsy date, serum creatinine levels at the time of biopsy, serum creatinine levels two years after biopsy, presence of erythrocyturia and proteinuria, and if the patient is on dialysis. CKDEPI (Chronic Kidney Disease Epidemiology Collaboration) equation adjusted for height and weight was used to estimate the glomerular filtration rate. Results: The research determined the highest prevalence of immunoglobulin A nephropathy and that this type of disease caused the highest deterioration of kidney function during a twoyear period after the biopsy. Pauci-immune glomerulonephritis had the highest mortality rate and statistically significantly worse kidney function two years after the biopsy compared to membranous glomerulonephritis. Conclusion: Kidney function can be predicted based on the pathohistological diagnosis of PGD two years after the biopsy.