40 nm WO3Pd composite film was sputtered on the sideface of sidepolished fiber Bragg grating (Dshaped FBG). The FBG sensing head with 40 nm WO3Pd composite film was firstly prepared by a 5 nm WO3 coating realized with radio frequency（RF）sputtering process, followed by depositing 5 nm WO3/Pd composite film, and then finished with 30 nm Pd film by directcurrent(DC) sputtering method. SEM results show that WO3Pd composite film still has good surface morphology after several cycle′s hydrogen response, which indicates WO3Pd composite film has good mechnical property. The experiment results demonstrate hydrogen sensor has good repeatability under different concentration hydrogen. Compared to standard FBG coated with same hydrogen sensitive film, the sensitivity of Dshaped FBG is increased by 200%. When the hydrogen concentration is 6% in volume, the wavelength shift of Dshaped FBG is about 15 pm. Dshaped FBG hydrogen sensor has great potential in hydrogen′s measurement.