Hojman conserved quantities deduced by using the special Lie symmetry, the Noether symmetry and the Mei symmetry for systems with non-Chetaev nonholonomic constraints in the event space are studied. First, the differential equations of motion for the above systems are established. Second, the criterion of the Lie symmetry, the Noether symmetry, the Mei symmetry and the relation between them are obtained. Third, the conservation law obtained by Hojman is generalized and applied to the systems, and Hojman conserved quantities are obtained. An example is given to illustrate the application of the results.