The acetone-sensing properties of the undoped and Pd doped perovskite-type oxides NdFeO3 were investigated from room temperature to 400℃.The perovskite-type NdFeO3 was synthesized by a sol-gel method,and the dopants Pd with the content from 1wt％ to 5wt％ were implanted into NdFeO3 nanoparticles by thermal diffusion.X-ray diffraction (XRD) and scanning electron microscopy (SEM)techniques show that NdFeO3 is an orthorhombic structure with the average particle size of about 40 nm.A giant acetone-sensing response of 675.7 is observed when the Pd content in NdFeO3 powders is about 3wt％.The response and recovery time of the sensor to the 5 × 10-4 acetone gas are 16 and 1 s,respectively.At the same time,it performs a good selectivity to acetone gas and may be a new promising material candidate for the acetone-sensor development.