Filgrastim is a recombinant therapeutic protein that acts as a human granulocyte- colony stimulating factor. It is primarily used to reduce the incidence and duration of severe neutropenia and associated complications. It is developed in Hospira, as a biosimilar according to Amgen Filgrastim. This paper describes the production of Filgrastim, designed according to human protein G-CSF, and its characteristics. Recombinant DNA technology techniques and the Escherichia coli cells are used for the production to obtain a protein similar to the human and preserve its properties. Filgrastim is produced by submerged cultivation of E.coli in several stages, under optimal physiological conditions. The production process is divided into four phases, which are growing vaccine I in Erlenmeyer flasks, then growing the vaccine II in the biosynthesis bioreactor of smaller volume, biosynthesis in bioreactor with the volume of 30 l, followed by separation and purification. Since the product is in the form of inclusion bodies, multiple separations by centrifugation are required, first of obtained biomass then inclusion bodies. In the production, the quality of water which is multiply purified is of great importance. Therefore, the water for injections was sampled and assessment of water quality was carried out.