Let G be a graph. Let be a function. If holds for each , then we call a fractional k‐factor of G with indicator function h where . A graph G is called a fractional ‐deleted graph if for every , there exists a fractional k‐factor of G with indicator function h such that , where H is any subgraph of G with m edges. In this paper, we obtain a toughness condition for a graph to be a fractional ‐deleted graph. This result is best possible in some sense, and it is an extension of Liu's previous result.