The dialkyl pentasulfide (DPS) - filled carbon nanotubes (CNTs) composites were successfully prepared by liquid phase wet chemistry method. Firstly, the CNTs were truncated with concentrated acid, and the end cap of CNTs was opened after the treatment. Under the liquid phase condition, the DPS was filled in the CNTs through the capillary force. Then, the composition and morphological structure of the samples were characterized by infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive spectrum (EDS) and thermogravimetric analysis (TG/DSC). The results showed that the DPS filled CNTs could be obtained by liquid-phase wet chemistry method. During the filling process, the DPS and the CNTs were mainly physical combinations, and the filling ratio of DPS was about 25%. The DPS was infiltrated into CNTs through a capillary effect and then protected by CNTs after the formation of the composites.