A process for the production of acrylonitrile by vapor phase catalytic ammoxidation of propylene in a fluidized bed at high yield with the use of a multicompenent fluidized bed catalyst comprising molybdenum, bismuth, iron, antimony, nickel and alkali metal(s) each carried by silica, which has a high catalytic activity and a high attrition resistance and which does not require any expensive cobalt catalytic component.