A novel kind of N -dimensional Lie algebra is constructed to generate multi-component hierarchy of soliton equations. In this paper, we consider a nonisospectral problem, from which we obtain a nonisospectral KdV integrable hierarchy. Then, we deduce a coupled nonisospectral KdV hierarchy by means of the corresponding higher-dimensional loop algebra. It follows that the K symmetries, τ symmetries and their Lie algebra of the coupled nonisospectral KdV hierarchy are investigated. The bi-Hamiltonian structure of the both resulting hierarchies is derived by using the trace identity. Finally, a multi-component nonisospectral KdV hierarchy related to the N -dimensional loop algebra is derived which generalize the coupled results to an arbitrary number of components.