ABSTRACT: Background Hypertension among young adults is common. However, the effect of isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), or systolic and diastolic hypertension (SDH) among young adults on chronic kidney disease (CKD) development is unknown. Methods and Results From a nationwide health screening database, we included 3 030 884 participants aged 20 to 39 years who were not taking antihypertensives at baseline examination in 2009 to 2010. Participants were categorized as having normal blood pressure (BP), elevated BP, stage 1 IDH, stage 1 ISH, stage 1 SDH, stage 2 IDH, stage 2 ISH, and stage 2 SDH. The primary outcome was incident CKD. A total of 5853 (0.19%) CKD events occurred. With normal BP as the reference, multivariable-adjusted hazard ratios (HRs) (95% CIs) for CKD were 1.14 (95% CI, 1.04-1.26), elevated BP; 1.19 (95% CI, 1.10-1.28), stage 1 IDH; 1.24 (95% CI, 1.08-1.42), stage 1 ISH; 1.39 (95% CI, 1.28-1.51), stage 1 SDH; 1.88 (95% CI, 1.63-2.16), stage 2 IDH; 1.84 (95% CI, 1.54-2.19), stage 2 ISH; 2.70 (95% CI, 2.44-2.98), stage 2 SDH. The HRs for CKD were attenuated in the patients who were antihypertensive and began medication within 1 year of medical checkup than in those without antihypertensives. Conclusions Among Korean young adults, those with elevated BP, stage 1 IDH, stage 1 ISH, stage 1 SDH, stage 2 IDH, stage 2 ISH, and stage 2 SDH were associated with a higher CKD risk than those with normal BP. The CKD risk in ISH and IDH groups was similar but lower than that in the SDH group. Antihypertensives attenuated the risk of CKD in young adults with hypertension.