Background: Evidence suggests lack of understanding of the association of specific nutrients with different time points of linear growth trajectory. Objective: We investigated the role of dietary macro- and micronutrients on length-for-age z (LAZ) score trajectory of children across first 24 months of their life. Methods: The MAL-ED Bangladesh birth cohort study recruited 265 healthy newborn children after birth. The linear growth trajectory of those children was modeled using latent growth curve modeling (LGCM) technique. Results: Dietary magnesium intake at 9 to 11 months was positively associated (coefficient β = 0.006, P < .02) with LAZ at 12 months. Animal protein intake at 15 to 17 months, in turn, was positively associated (β = 0.03, P < .03) with LAZ at 18 months. However, vitamin D intake at 15 to 17 months was negatively associated (β = −0.06, P < .02) with LAZ at 18 months. Other micro- and macronutrients did not show any statistically significant association with the linear growth trajectory. We also found that birth weight (β = 0.91, P < .01), treating water (β = 0.35, P < 0.00), and maternal height (β = 3.4, P < .00) were positively associated with intercept. Gender had a significant negative association with the intercept, but a positive association with the slope (β = −0.39, P < .01; β = 0.08, P < .04), respectively. Conversely, birth weight had negative association with the slope (β = −0.12, P < .01). Conclusions: Dietary magnesium and animal protein were positively and vitamin D was negatively associated with the linear growth trajectory. Maternal height, birth weight, gender, and treatment of drinking water also played significant roles in directing the trajectory.