Hydrogenation disproportionation desorption and recombination (HDDR) magnets prepared from RE16Fe76-xB8Zrx alloys (RE: Nd, Pr; x=0-0.5) have been investigated in the present work. The effect of HDDR processing parameters, heat treatments, alloy composition and casting condition on the magnetic properties have been studied: It has been shown that the higher degree of anisotropy has been induced in the Nd-based alloy with 0.1 at% of zirconium. The optimum processing temperature for this alloy was close to 860 degreesC.