The present invention relates to an antibody for cancer treatment and provides an anti-CD43 antibody which binds an extracellular region of CD43 consisting of 6-9 amino acids in the amino acid sequence EGSPLWTSI, an anti-cancer composition and a composition for inhibiting cancer stem cells comprising the anti-CD43 antibody as an active ingredient, and a method for screening a cancer stem cell inhibitor. The anti-CD43 antibody comprises: heavy chain CDRs according to GYXMN (wherein X is F or Y), RINPNXGDSFYNQKFXG (wherein the first X is N or S； and the second X is Q or K), and EGYYGGRGYALDY； and light chain CDRs according to RTSQDISNYLN, XTXRLHS (wherein the first X is N, Q or A； and the second X is S or A), and QQSNMFPY.
