Let Ω be the unit ball centered at the origin in R N (N ≥ 4), 2 * = 2N N −2 , τ > 0, ε > 0. We study the following problemBy a constructive argument, we prove that for any k = 1, 2, · · ·, if ε is small enough, then the above problem has positive a solution uε concentrating at k distinct points which tending to the boundary of Ω as ε goes to 0 + .