Colony collapse disorder is a phenomenon, which causes rapid decline in bee colonies. It is a global problem for bees and beekeepers. Although the origin and mechanism of this process is still not know, one of the agents, which cause the collapses are virus infections. One of these viruses is chronic bee paralysis virus (CBPV), a positive single strained RNA virus. We aim to determine the structure of CBPV RNA-dependent-RNA-polymerase. We used E. coli bacterial expression system, as well as, baculovirus expression system in SF9 cell line, which is more phylogenetically related to bees, the natural hosts of CBPV. We found significant differences in solubility of CBPV RNA polymerase produced by these expression systems. Partial solubility of recombinant CBPV RNA polymerse produced by SF9 cell line enabled further experiments leading to the preparation of pure protein, its crystallization, and subsequent structure determination. Knowledge of the structure of CBPV RNA polymerase may allow development of anti-viral compounds.