Amorphous and nanostructural Fe-B alloys made by mechanical alloying of elemental Fe and amorphous B powders have been studied using X-ray diffraction, differential scanning calorimetry and Mossbauer spectroscopy. It has been shown that the milling conditions have a strong effect on the alloying. The single phase amorphous alloy, which is limited at nominal composition of Fe60B40, has been produced only by milling in Ar atmosphere and in other composition range the mixture of nanostructure Fe-like phase and Fe2B compound with a little amorphous phase are obtained. While by milling in air atmosphere the introduction of oxygen in air may suppress the formation of amorphous phase, thus the compounds Fe2B may be synthesized with no trace of amorphous phase. The crystallization temperatures of amorphous phase in the resultant products are higher than those of a single amorphous alloy Fe60B40, and hardly independent of the milling conditions and the composition. In addition, it is revealed that detectable B content in the final products is lower than the nominal composition of all the initial samples, which indicates that some B atoms may be located in the disordered interfacial regions of the nanostructural alloyed mixtures. Amorphous and nanostructural Fe-B alloys made by mechanical alloying of elemental Fe and amorphous B powders have been studied using X-ray diffraction, differential scanning calorimetry and Mossbauer spectroscopy. It has been shown that the milling conditions have a strong effect on the alloying. The single phase amorphous alloy, which is limited at nominal composition of Fe60B40, has been produced only by milling in Ar atmosphere and in other composition range the mixture of nanostructure Fe-like phase and Fe2B compound with a little amorphous phase. milling in air atmosphere the introduction of oxygen in air may suppress the formation of amorphous phase, thus the compounds Fe2B may be synthesized with no trace of amorphous phase. The crystallization temperatures of amorphous phase in the resultant products are higher than those of a single amorphous alloy Fe60B40, and hardly independent of the milling conditions and the composition. In addition, it is revealed t hat detectable B content in the final products is lower than the nominal composition of all the initial samples, which indicates that some B atoms may be located in the disordered interfacial regions of the nanostructural alloyed mixtures.