The development of protein-based biotechnology and drugs holds tremendous potential for various applications. However, the effective intracellular delivery of natural proteins remains a challenge due to their inability to spontaneously penetrate the cell membrane. In this study, we have developed a modular fusion protein sequence that overcomes this limitation and enables efficient cytoplasmic protein delivery . This modular fusion protein we designed has demonstrated efficient lysosomal escape ability, allowing for successful delivery of various protein cargoes into the cytoplasm of different cell types. Importantly, the fusion with the mCherry tag does not affect the biological activity of the protein. The fusion protein can still exert its catalytic activity when delivered into cells. We also designed a fluorescent protein probe capable of precisely targeting lysosomes, providing powerful fluorescent probe tools for intracellular localization and tracking in biomedical research. This approach contributes to the advancement of protein drug development and opens up new possibilities for therapeutic interventions.