Chlamydomonas reinhardtii is a novel recombinant eukaryotic expression system with many advantages including fast growth rate, rapid scalability, absence of human pathogens and the ability to fold and assemble complex proteins accurately, however, obstacle relatively low expression level necessitates optimizing foreign gene expression in this system. The Green Fluorescent Protein (GFP) from the jellyfish Aequorea victoria is a substantial reporter molecule for monitoring gene expression and protein localization.The fluorescence of GFP requires only UV or blue light, and, therefore, the in vivo observation of GFP expression is easy with no need for complex and costly apparatus.