Fabrication of hybridized single-walled carbon nanotube (SWNT) device based on novel sensing material N-4-Hexafluoroisopropanolphenyl-1-pyrenebutyramide (HFIPP) via facile approach has been reported for the first time. Considered that strong hydrogen-bonding can be formed between HFIPP and dimethyl methylphosphonate (DMMP) (simulant of nerve agent sarin), the HFIPP-decorated SWNT device has been employed to detect DMMP. The detection limit achieved with our sensor is as low as 50 ppb; moreover, the response and reproducibility can be presented clearly even at very low concentration of DMMP. Excellent sensitivity and selectivity of the hybridized SWNT-HFIPP device suggest that it has great potential application for detecting explosives and nerve agents. In order to investigate sensing mechanism of SWNT-HFIPP for DMMP, control electrical and fluorescent experiments have been carried out and discussed in the present paper.