Background and Objectives: Information on the growth status of indigenous children is useful for developing intervention strategies, but the data are limited. This study determined the prevalence of undernutrition among under-five indigenous children (Orang Asli) and tracked the growth status of Orang Asli children aged 0–3 years. Methods and Study Design: This study had two phases: a cross-sectional growth study of under-five Orang Asli children (N=304; Phase 1) and a 2-year prospective cohort growth study of Orang Asli children aged 0–3 years (N=214; Phase 2) in the Temerloh district of Pahang, Malaysia. Weight-for-age, length/height-for-age, weight- for-length/height, and body mass index-for-age were determined. Results: The prevalence rates of stunting, un- derweight, wasting, and thinness in under-five Orang Asli children (Phase 1) were 64%, 49%, 14%, and 12%, re- spectively. In the cohort of 214 children (Phase 2), weight-for-age was initially documented and maintained closely at −1.50 standard deviations (SD) in the first 6 months, but it declined to approximately −2.00 SD at 15 months and remained close to −2.00 SD thereafter. Length/height-for-age declined rapidly to approximately −2.50 SD at 18 months and fluctuated between −2.30 and −2.50 SD thereafter. Weight-for-length/height in- creased sharply to −0.40 SD at 2–3 months, declined gradually to less than −1.00 SD at 12 months, and plateaued between −1.00 and −1.30 SD thereafter. Conclusions: Undernutrition is prevalent among Orang Asli children, with length rather than weight faltering being more pronounced in the first 2 years of life. Identifying the causes of early growth retardation in this population is required to inform future preventive strategies.