This paper is devoted to giving sharp time estimates for local exact boundary controllability of 1-D homogeneous quasilinear hyperbolic systems. We improve the time for the boundary controllability proposed by Li [Controllability and Observability for Quasilinear Hyperbolic Systems, AIMS Appl. Math. 3, American Institute of Mathematical Sciences (AIMS), Springfield, MO; Higher Education Press, Beijing, 2010, Thms. 3.2 and 3.3, pp. 39-41] and Zhang [Appl. Math. J. Chinese Univ. Ser. A, 24 (2009), pp. 65-74 (in Chinese)] both for the case of one-sided control and for the case of two-sided control when the dimension of the controls is the same as in the case of onesided control. Our approach relies on the utilization of constructive methods and the characteristic theory together with a suitable iteration scheme on a suitable time interval.