Objective: We analyzed the data of prospective CKD patient cohort, namely SKETCH (Study on Kidney disease and EnviromenTal Chemicals, Clinical Trial. No NCT04679168). The SKETCH cohort includes CKD patients who visited the participating hospitals at first time between June and October, 2020, and at second time between October, 2020 and January, 2021. Demographic data, socioeconomic and behavioral characteristics, which is practicing social distancing, hygienic behavior, and physical activity, from questionnaire survey at first and second visit were included. Methods: In the total population, nine out of twelve behaviors were reinforced at the first visit, and five out of nine reinforced behaviors were weakened at the second visit. Individual high risk perception was not associated with tendency of overall behavioral reinforcement or to maintain behaviors in an enhanced state at the second visit. Previously strong behavioral change was associated with tendency of strengthening for maintaining reinforced overall behaviors at the second visit (adjusted odds ratio 1.99, 95% confidence interval 1.19-3.37, p-value 0.009). Results: Even if the initial COVID-19 risk perception is high, behavioral changes worsen over time, and people who showed more active behavioral changes at the beginning showed a tendency to maintain reinforced behavior over time. Continuous education and monitoring are needed for patients who had even high initial COVID-19 risk perception. Conclusions: Objective: In chronic kidney disease (CKD) patients, coronavirus disease-2019 (COVID-19) has a higher mortality than the general population, so the prevention is more important. To prevent COVID-19 infection, it is important to change individual infection avoidance behavior. To figure out how behavioral characteristics in social distancing, hygiene management, and exercise change after COVID pandemic in CKD patients, and identify the characteristics of people who showed weakened or strengthened behavioral changes   Methods: We analyzed the data of prospective CKD patient cohort, namely SKETCH (Study on Kidney disease and EnviromenTal Chemicals, Clinical Trial. No NCT04679168). The SKETCH cohort includes CKD patients who visited the participating hospitals at first time between June and October, 2020, and at second time between October, 2020 and January, 2021. Demographic data, socioeconomic and behavioral characteristics, which is practicing social distancing, hygienic behavior, and physical activity, from questionnaire survey at first and second visit were included. Results: In the total population, nine out of twelve behaviors were reinforced at the first visit, and five out of nine reinforced behaviors were weakened at the second visit. Individual high risk perception was not associated with tendency of overall behavioral reinforcement or to maintain behaviors in an enhanced state at the second visit. Previously strong behavioral change was associated with tendency of strengthening for maintaining reinforced overall behaviors at the second visit (adjusted odds ratio 1.99, 95% confidence interval 1.19-3.37, p-value 0.009). Conclusions: Even if the initial COVID-19 risk perception is high, behavioral changes worsen over time, and people who showed more active behavioral changes at the beginning showed a tendency to maintain reinforced behavior over time. Continuous education and monitoring are needed for patients who had even high initial COVID-19 risk perception.