The present invention provides a catalyst composition for preparing an amide, including an amino acid ionic liquid having a cation of formula (I) and an anion selected from the group consisting of an inorganic acid group, an organic acid group and a combination thereof, wherein the numbers of the anion and the cation are such that the amino acid ionic liquid is electroneutral; and a Bronsted acid. The present invention also provides a method for preparing an amide in the presence of the catalyst composition, and the method has advantages such as decreasing viscosity of ionic liquid, and increasing conversion rate of ketoximes and selectivity of amides.