Recently, several cell-surface conjugation methods have been developed to manipulate cellular interactions for exploiting various cell-based applications. Still, live-cell surface modification remains challenging because of a lack of chemically reactive functional groups on many cell surfaces and the dynamic structure of the plasma membrane. Poor stability of the conjugated linker on a cell surface is also another problem for long-term application. Other methods to install non-natural functional groups on cell surfaces via metabolic docking takes several days to express those functional groups. Thus, there is a need to develop a facile and general method for live cell surface functionalization without altering the function of the cells. Here, we provide a general cell surface conjugation strategy using the native phosphate groups on the cell membrane. We have decorated one side of the cargo molecule with a cationic functionality to facilitate non-covalent interaction with the negatively charged cell surface and the other side of the cargo molecule with a phosphoric acidcontaining ligand such as adenosine diphosphate (ADP) to facilitate phospho-ester covalent bonds under the physiological condition with the cell surface phospholipid phosphate functionalities. Our dual chemical conjugation approach provides longer stability of the cell surface conjugation and shows no effect on viability due to the formation of the natural phospho-ester bond instead of unnatural chemical reactions.