A ferrite powder for bonded magnets having a substantially magnetoplumbite-type crystal structure and an average diameter of 0.9-2 nullm, the ferrite powder having a basic composition represented by the following general formula: (A1-xRx)O.nnull(Fe1-yMy)2O3null by atomic ratio, wherein A is Sr and/or Ba; R is at least one of rare earth elements including Y, La being indispensable; M is at least one element selected from the group consisting of Co, Mn, Ni and Zn; and x, y and n are numbers meeting the conditions of 0.01nullxnull0.4, nullx/(2.6n)nullnullynullnullx/(1.6n)null, and 5nullnnull6, (SinullCa) being 0.2 weight % or less, and (AlnullCr) being 0.13 weight % or less, can be produced by mixing iron oxide containing 0.06 weight % or less of (SinullCa) and 0.1 weight % or less of (AlnullCr) with compounds of A, R and M elements, calcining the resultant mixture for ferritization, pulverizing the resultant magnetically isotropic ferrite and then heat-treating the pulverized ferrite at 750-950null C. for 0.5-3 hours in the air.