We analyzed the 11Li(p,p’) reaction at 6 MeV/nucleon by using a microscopic continuum-discretized coupled-channels method, in which 11Li is described by a 9Li + n + n three-body model. In this analysis, we found a dipole resonance of 11Li, and the resonance can be interpreted as a bound state in the 10Li + n system, that is , a Feshbach resonance in the 9Li + n + n system. For 11Li, the 10Li + n threshold is open above 9Li + n + n one, which reflects a distinctive property of the Borromean system. Thus we refer to this resonance as a Borromean Feshbach resonance. The calculated cross sections by taking into account the resonance and nonresonant continuum reproduce the experimental data recently observed. In this conference, we will show the results and discuss properties of the Borromean Feshbach resonance.