Arginine-rich peptides are a promising source of membrane-permeable peptides that can serve as carriers for intracellular protein delivery. This study demonstrates that various arginine-rich peptides, including those derived from HIV-1 Tat, HIV-1 Rev, FHV coat proteins, and DNA-binding segments from c-Fos, c-Jun, and GCN4, can translocate through cell membranes and accumulate in the nucleus. These peptides exhibit similar translocation activity to the HIV-1 Tat-(48–60) peptide, which is known for its ability to deliver proteins into cells. The internalization of these peptides is not inhibited by low temperatures, suggesting a mechanism different from typical endocytosis. The study also shows that the number of arginine residues in the peptides affects their translocation efficiency, with an optimal number of around 8 arginine residues for efficient translocation. The results suggest that arginine-rich peptides may have a common internalization mechanism that is not explained by traditional endocytosis. The study also demonstrates the ability of these peptides to deliver proteins such as carbonic anhydrase into cells, highlighting their potential as carriers for intracellular protein delivery. The findings suggest that arginine-rich peptides could be useful for therapeutic applications and for understanding fundamental cellular processes.Arginine-rich peptides are a promising source of membrane-permeable peptides that can serve as carriers for intracellular protein delivery. This study demonstrates that various arginine-rich peptides, including those derived from HIV-1 Tat, HIV-1 Rev, FHV coat proteins, and DNA-binding segments from c-Fos, c-Jun, and GCN4, can translocate through cell membranes and accumulate in the nucleus. These peptides exhibit similar translocation activity to the HIV-1 Tat-(48–60) peptide, which is known for its ability to deliver proteins into cells. The internalization of these peptides is not inhibited by low temperatures, suggesting a mechanism different from typical endocytosis. The study also shows that the number of arginine residues in the peptides affects their translocation efficiency, with an optimal number of around 8 arginine residues for efficient translocation. The results suggest that arginine-rich peptides may have a common internalization mechanism that is not explained by traditional endocytosis. The study also demonstrates the ability of these peptides to deliver proteins such as carbonic anhydrase into cells, highlighting their potential as carriers for intracellular protein delivery. The findings suggest that arginine-rich peptides could be useful for therapeutic applications and for understanding fundamental cellular processes.