An Fe--Co--B alloy target, in which the largest inscribed circle depictable in regions containing no boride phases in its cross-sectional microstructure has a diameter of 30 .mu.m or less. Its composition is represented by (Fe.sub.XCo.sub.100-X).sub.100-YB.sub.Y (by atomic percentage), wherein 5.ltoreq.X.ltoreq.95, and 5.ltoreq.Y.ltoreq.30.