Objectives: COVID pandemic is related to psychological distress and the distress depends on various factors. We have previously reported that hemodialysis patients had more psychological distress than peritoneal dialysis patients in CKD patients on dialysis in the era of COVID pandemic. However, no study has reported how psychological distress related to COVID-19 depends on renal function in the entire group of CKD patients. Therefore, this study investigated psychological distress and concerns related to COVID-19 according to CKD grade. Methods: This was a cross-sectional study that included 397 CKD patients who visited Soonchunhyang University Cheonan Hospital from August 2020 to November 2020. Patients responded to questionnaires covering depression (9-item Patient Health Questionnaire, PHQ-9), anxiety (7-item Generalized Anxiety Disorder, GAD-7), psychological impact of event (22-item Impact of Event Scale-Revised, IES-R), insomnia (7-item Insomnia severity Index, ISI), and concerns about COVID-19. Patients were divided into three groups -patients with CKD grade 1~2, patients with CKD grade 3~5 without dialysis, and dialysis patients- according to eGFR and dialysis status. Jonckheere-Terpstra test and linear by linear association were used. Results: The higher the CKD grade, the higher GAD-7 (p=0.009) and ISI score (p=0.001). When patients with CKD grade 1~2 and patients with CKD grade 3~5 (with or without dialysis) were compared, PHQ-9 (p=0.026), GAD-7 (p=0.010), and ISI score (p=0.002) were higher in CKD grade 3~5 group. However, only the ISI score (p=0.008) showed a significant difference depending on dialysis. Conclusions: CKD patients showed more psychological distress as renal function worsened during the COVID-19 pandemic. Therefore, as CKD grade increases, more attention should be paid to mental care of these patients.