Abstract: The objective of the study was to assess the impact of an alimentary integrator composed by Spiruline (Spirulina platensis), produced at the Centre Medical St Camille (CMSC) of Ouagadougou, Burkina Faso, on the nutritional status of undernourished HIV-infected and HIV negative children. We compared two groups of children: 84 children HIV-infected and 86 HIV-negative. The duration of this study was eight weeks. Anthropometrics and haematological parameters allowed us to appreciate both the nutritional and biological effects of Spiruline supplement to traditional meals. The rehabilitation with Spiruline shows on average a weight gain of 15 and 25 g/day in HIV-infected and in HIV negative children, respectively. The level of anaemia decreased during the study in all the children, but the recuperation was less efficient among the HIV-infected children, in fact, 81.8% of HIV negative undernourished children recuperated against 63.6% of HIV-infected children [Z: 1.70 (95% CI: -0.366, -0.002, p=0.088)]. Present results allow to confirm that Spiruline is a good food supplement for undernourished children. In particular the rehabilitation by Spiruline seems to correct the anaemia and the weight loss also in HIV-infected, but more quickly in HIV negative undernourished children.