  We provide an algebraic way to calculate the quasi-normal modes of a black
hole, which possesses a hidden conformal symmetry. We construct an infinite
tower of quasi-normal modes from the highest-weight mode, in a simple and
elegant way. For the scalar, the hidden conformal symmetry manifest itself in
the fact that the scalar Laplacian could be rewritten in terms of the $SL(2,R)$
quadratic Casimir. For the vector and the tensor, the hidden conformal symmetry
acts on them through Lie derivatives. We show that for three-dimensional black
holes, with appropriate combination of the components the radial equations of
the vector and the tensor could be written in terms of the Lie-induced
quadratic Casimir. This allows the algebraic construction of the quasi-normal
modes feasible. Our results are in good agreement with the previous study.
