Neutron diffraction studies of HoFeO3 single crystals were performed under external magnetic fields. The interplay between the external magnetic fields, Dzyaloshinsky-Moria antisymmetric exchange, isotropic exchange interactions between Fe and Ho sublattices and within the Fe sublattice provides a rich magnetic phase diagram. As the result of the balance of exchange interactions inside the crystal and external magnetic fields, we found 8 different magnetic phases, induced or suppressed dependent on the external field.