Summary: Bioluminescence tomography (BLT) is a recently developed noninvasive imaging tool that allows a direct study of the molecular activity in small animal models. While the forward problem is reduced to a diffusion equation since the scattering phenomena are dominated by the absorption ones in biological tissues, the reconstruction of the distribution of the BLT source is an inverse source problem. In this paper, we concentrate on the reconstruction method where we present an algebraic method allowing to identify the number, the intensities and the location of monopolar sources. Finally, some numerical results are shown proving the robustness of the method.