Engineering of algal cells by delivering macromolecules through cell wall and plasma membrane presents many difficulties with the conventional methods. Recent research has shown that a new delivery method, namely cell penetrating peptide (CPP), has the ability to translocate into animal, plant, fungal, and bacterial cells. This study reports the apparent translocation of CPPs into algal cells of Chlamydomonas reinhardtii and the successful delivery of the conjugated fluorochrome. Although translocation efficiency was specific to each CPP studied, pVEC (peptide vascular endothelial cadherin) showed the highest translocation efficiency in comparison with penetratin (PEN), trans-activating transcriptional (TAT) peptide, and transportan (TRA). The maximum translocation of pVEC into the algal cell was reached in 15min of incubation at 25 degrees C. More importantly, translocation with pVEC demonstrated an absence of cytotoxicity. Thus, we suggested that pVEC is an attractive candidate for delivering macromolecules into algal cells for use in industrial applications. Biotechnol. Bioeng. 2013;110: 2795-2801. (c) 2013 Wiley Periodicals, Inc.