Abstract Background and Aims Unhealthy life-behaviors such as dietary habits, lack of exercise, drinking large amount of alcohol and smoking cause obesity, hypertension, diabetes, dyslipidemia, cardiovascular disease (CVD). These are also closely associated with chronic kidney disease (CKD). CKD is characterized by proteinuria and low glomerular filtration rate (GFR). Independent of GFR, proteinuria is an important predictor of ESKD. Few studies have assessed which is the most clinical impact among the unhealthy life-behaviors: skipping breakfast, snacking, late-night dinner, smoking, heavy alcohol intake and lack of exercise habits for proteinuria in normal renal function patients. Method This cross-sectional study included 29,780 normal renal function patients: eGFR≥60 mL/min/1.73 m2 and no history of kidney diseases who underwent health checkup at the Physical Checkup Center of Sumitomo Hospital. The endpoint of this investigation is defined as dipstick proteinuria of≥ 1+. To assess the association of life-behaviors and the presence of proteinuria, their odds ratios were calculated in adjusted univariable and multivariable logistic regression model. Multivariable logistic regression model was performed by not selected items, the same with univariable model. We would like to investigate the most impact unhealthy life-behavior for the proteinuria. Results Among 29,780 total study subjects (male: 60.3%; mean age: 49±11 years), 1,118 (3.75%) subjects were shown as urinary protein above 1+. The presence of unhealthy dietary life-behaviors: skipping breakfast, snacking and late-night dinner was 5,293 (17.3%), 3,899 (13.1%) and 11,231 (37.7%), respectively. About sleeping duration, the population of <6 hours, 6-8 hours and >8 hours were 12,027 (40.4%), 17,236 (57.9%) and 517 (1.7%). The population of exercise habits: over 3 days/weeks, 1-2 days/weeks and none were 5,138 (17.3%), 9,375 (31.5%) and 15,237 (51.3%), suggesting half of them did not have exercise habits. About smoking habits, the population of current smoking, past smoking and never smoking were shown 6,445 (21.6%), 8,459 (28.4%) and 14,876 (50.0%). In addition, about alcohol amount per day, the population of over 60g, 40-60g, 20-40g and 0-20g were 1,840 (6.18%), 4,504 (15.1%), 6,727 (22.6%) and 16,709 (56.1%). To investigate the impact of life-behavior for proteinuria, we obtained odds ratio of adjusted multivariable logistic regression model. In multivariable regression, among the life-behavior: skipping breakfast, current smoking, alcohol amount (ethanol over 60 g/day), none of exercise habits and snacking were strongly associated with the prevalence of proteinuria (skipping breakfast, adjusted odds ratio 1.45 [1.26, 1.68]; current smoking, 1.35 [1.14, 1.59]; alcohol amount (ethanol over 60 g/day), 1.35 [1.08, 1.69]; none of exercise habits, 1.29 [1.07, 1.57]; snacking, 1.23 [1.04, 1.46]). In addition, among the history of medical history, diabetes mellitus, hypertension and dyslipidemia were significantly associated with the prevalence of proteinuria (diabetes mellitus, adjusted odds ratio 2.39 [1.93, 2.96]; hypertension, 1.83 [1.53, 2.17]; 1.22 [1.03, 1.45]). Conclusion Among the unhealthy life-behaviors, skipping breakfast is the most impact factor for the presence of proteinuria.