The effect of heat treatment and binder additions on the magnetic behavior of P/M(powder metallurgy) processed Fe73.5Si13.5B9Cu1Nb3 alloy has been investigated. FeSiBCuNb amorphous ribbons produced by plannar flow casting were annealed at temperatures between 480degreesC and 620degreesC for 20 to 60 minutes. The annealed specimens were milled using a pin crusher and a hammer mill. The powder was then mixed with mineral or polymer binders to press into a toroidal shape of inductor core at room temperature. Fe73.5Si13.5B9Cu1Nb3 alloy showed maximum permeability when annealed at 540degreesC for 40 minutes. The microstructure of the annealed ribbon has a ultra-fine alpha-Fe(Si) grain, ranging from 10 to 20 nm in diameter. Inductor cores produced using a glass binder showed better magnetic proper-ties than polymers or oxide binders. The use of mineral binders in producing nanocrystalline inductor cores significantly improved magnetic properties, compared to a commercial moly-permalloy powder core.