We try to generalize an explicit construction for an orthonormal system of eigenfunctions of the Vladimirov operator on L 2 ( ℚ p n ) which was originally given by Vladimirov (1988). Also the multiwavelet analysis can be considered as the p -adic spectral analysis in L 2 ( ℚ p n ) , using in part the recent work of Kozyrev (2002).