The effects of partial substitution of cobalt for iron and small addition of Zr in the Nd-Fe-B system were studied. The results obtained were as follows: 1) The curie temperature increases linear with increasing cobalt content in the Nd-Fe-Co-B-Zr system. 2) In this system Nd₂(Fe.Co)_(14) B matrix phase, Nd rich phase and Zr rich phase were confirmed. 3) The Zr content in matrix is small regardless original addition of Zr in the system. 4) Magnetic properties such as (BH) max; 39MGOe, Br; 13.3 KG and iHc; 5.8 KOe were achieved in Nd-Fe-Co-B-Zr magnet.