The binding energy Eb of the acceptor–exciton complex (A−,X) as a function of the radius (or of the impurity position of the acceptor) and the normalized oscillator strength of (A−,X) in spherical ZnO quantum dots (QDs) embedded in a SiO2 matrix are calculated using the effective-mass approximation under the diagonalzation matrix technique, including a three-dimensional confinement of the carrier in the QD and assuming a finite depth. Numerical results show that the binding energy of the acceptor–exciton complexes is particularly robust when the impurity position of the acceptor is in the center of the ZnO QDs.