Abstract: A kind of biomimetic amphoteric polymer, phosphatidylcholine (PC), was used as surfactant to produce water soluble and biocompatible magnetic carbon nanotubes (Fe₃O₄/CNTs), which was prepared by solvothermal method. Fe₃O₄/CNTs was facilely dispersed in aqueous media by ultrasonication with the help of PC, with the long hydrophobic segment and the hydrophilic group as controls. The biological properties of the PC modified Fe₃O₄/CNTs (Fe₃O₄/CNTs-PC) were evaluated using protein adsorption assay and recalcification time. The results indicate that the adsorption capacity of bovine serum albumin (BSA) is 0.1368 mg/mg, and the recalcification time is 324 s. These experimental results suggest that Fe₃O₄/CNTs-PC has good outstanding biocompatibility.