This study advances knowledge of developmental patterns in poverty and delinquency; data was obtained from waves 1-5 (2003-2007) of the Korea Youth Panel Survey. Semi-parametric group-based modeling (SGM) identified 4 trajectories of poverty from age 13 to 17 : non-poor, poverty increasing, low-level continuous poverty and chronic poverty groups and five developmental trajectories of delinquency : non-offending, late onset, low-level continuous, desisting, and chronic groups. A joint trajectory method predicted patterns of delinquency conditional on poverty trajectories. Chronic and low-level continuous poverty groups were more likely than others to follow chronic trajectories of delinquency; the non-poor group was more likely to be non-offending. Implications of this study for youth welfare were discussed to reduce risk for delinquency.