Aiming at the low drilling efficiency and short service life of bit for drilling in hard and compact rocks and the high price of conventional matrix materials for diamond bit, the paper introduced mixing regression design method. Experimental study was made on the replacement of tungsten carbidebased matrix with a new ironbased matrix material; analysis was made on the relationship between the diamond exposure of hotpressed bit and rock abrasiveness properties, the matrix components and the performances were determined to be important. Based on the study of matrix components and performances of hot pressed diamond bit, high phosphorus iron based matrix material was developed and diamond bits with this kind of alloy as matrix were manufactured. The results of indoor drilling test on rock with drillability of grade Ⅸ showed that the average penetration rate reached 1.91m/h and average service life was 60.26m. Therefore, high phosphorus iron based matrix is a economical choice with good performance.