In this paper, we introduce a concept of RC-positivity for Hermitian holomorphic vector bundles and prove that, if E is an RC-positive vector bundle over a compact complex manifold X, then for any vector bundle A, there exists a positive integer cA = c(A, E) such thatfor ℓ ≥ cA(k + 1) and k ≥ 0. Moreover, we obtain that, on a compact Kähler manifold X, if Λ p TX is RC-positive for every 1 ≤ p ≤ dim X, then X is projective and rationally connected. As applications, we show that if a compact Kähler manifold (X, ω) has positive holomorphic sectional curvature, then Λ p TX is RC-positive and H p,0 ∂ (X) = 0 for every 1 ≤ p ≤ dim X, and in particular, we establish that X is a projective and rationally connected manifold, which confirms a conjecture of Yau ([57, Problem 47]).