The goal of this short-term longitudinal study was to examine the functioning of the grit measure; grit's relation to emotional engagement; and grit's prediction of later literacy achievement, above and beyond emotional engagement, among dual language learners. Data were collected at two time points four months apart with dual language learner, third- through fifth-grade students (n = 142; 75% Latina/o; mean age 9.47 years old; 54% female). Results suggested that student- and teacher-reported grit scores were reliable and fit the two-factor construct, and grit overlapped with engagement. We found that teacher-reported engagement and student- and teacher-reported grit perseverance of effort (grit-pe) were significant sole predictors of Time 2 literacy achievement; teacher-reported engagement, not grit, remained a significant sole predictor even when controlling for Time 1 literacy achievement. When including grit-pe, grit consistency of interests, and engagement in the same model, student-reported grit-pe was the only significant predictor of Time 2 literacy achievement, without Time 1 literacy as a control. Discussion centers on grit-pe's utility for prediction of literacy achievement, above and beyond similar socioemotional constructs, among young dual language learners.