Indian tribal people account for 8.14 per cent of the total population of the country, numbering 84.51 million (Census, 2001). There were 635 tribal groups including 75 designated as ‘primitive’ based on pre-agricultural level of technology, low literacy, diminishing population size, relative seclusion from the main stream of population, economical backwardness, extreme poverty, dwelling in remote inaccessible hilly terrains, maintenance of constant touch with the natural environment, and unaffected by the developmental process undergoing in India. There is a consensus that these scheduled tribes are the descendants of aboriginal population in India. Using Random sampling method, 4376 PTG Children in the age group of 1 –14 years from Nilgiris were screened clinically for symptoms of VAD, IDA and other micronutrient deficiencies. Among them, 84 children showing moderate to severe clinical symptoms of VAD and IDA in the age group of 7- 14 years were selected for the Spirulina supplementation for a period of 180 days. The clinical observations revealed that the prevalence of VAD and IDA is beyond the cutoff points of WHO standards and thereby making it a problem of public health significance among the screened PTG children. Spirulina supplementation showed a significant impact on clinical symptoms, nutritional anthropometry, serum retinol and blood haemoglobin when compared to placebo.