Nanocrystalline soft magnetic materials are interesting from both the fundamental and applied viewpoints. Because of various superior mechanical, magnetic and electrical properties, in comparison with those of the crystalline state, these alloys (metallic glasses) form a class of technologically important materials. In order to study the effect of Nb on the magnetotransport properties of the nanocrystalline soft magnetic material (Fe0.9Co0.1)73.5-Cu1-Nb3-Si13.5-B9, temperature and field dependent resistivity as well as magnetoresistance have been measured using conventional four-probe technique. This alloy exhibits metallic behavior in the high temperature range due to the formation of microcrystallites around the crystallization temperature Tx since more and more conduction electrons participating in the conduction mechanism. The value of magnetoresistance is found to vary (1~15%) at different temperatures (28°C~ 240°C). The complex permeability of this magnetic alloy has been measured for both as cast and annealed samples. Permeability measurement has been taken at low frequency (1 KHz-13 MHz). The permeability is found to be in the order of 104. The real part of the complex permeability is found to increase while the imaginary part is found to decrease with annealing temperatures due to local segregations. The best response is obtained for the sample annealed at 450°C for 5 minutes only. The overall permeability of the sample has low value when annealed at 450°C for 1 hour. The frequency range where the sample can be useful as a soft magnetic material is found out as 10 KHz to 1MHz. The magnetization of the sample has been measured as a function of magnetic field at room temperature (28°C) using a vibrating sample magnetometer (VSM). Saturation magnetization for the sample is observed to be around 179 emu/gm.