This paper deals with spectrum and Riesz basis assignability of infinite-dimensional linear systems via bounded linear feedbacks. The necessary and sufficient condition of Sun [SIAM J. Control Optim., 19 (1981), pp. 730-743] is generalized to a large class of boundary control systems. Two typical examples are presented to illustrate the application of our results. The results obtained in this paper may have potential applications in nondissipative spectral systems.