The demand for recombinant proteins has steadily increased and the production of such recombinant proteins in heterologous systems has improved significantly in recent years. Most applications involve difficult to produce proteins including complex proteins and glycoproteins thus promoting the development and improvement of a wide range of production platforms. For the production of all recombinant proteins no individual system is optimal, so the diversity of platforms based on different host-vector systems has been developed. Here, we discuss the most commonly used production platforms based on the bacteria, several species of yeast, and a selection of mammalian cell lines production highlighting their unique advantages and disadvantages. The significance of mammalian host system like CHO and its unique advantages and disadvantages are highlighted in this review.