Iodine deficiency disorder (IDD) remains a significant global public health problem. The aim of this study was to assess the prevalence of IDD amongst Orang Asli in semi-urban areas. A cross sectional study was conducted in April of 2006 in whom 346 children and adult women participated. UIC was performed in 97 (28.0%) pre-school children (PSC) aged 1-6 years old, 115 (33.2%) primary school going children (SGC) aged 7-12 years old and 134 (38.8%) adult women (≥ 15 years old). The median UIC of the studied population was 45.11 µg/L while the median UIC was 49.43 µg/L, 47.81 µg/L and 38.98 µg/L for PSC, SGC and adult women respectively. Moderate to severe IDD was present in 50% of PSC, 53.9% of SGC and 70.1% of adult women. Therefore, the Universal salt Iodization (USI) approach may have eliminate IDD in the areas.