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< p > The electron paramagnetic resonance (EPR) parameters g(i)-factors (i = x, y, z) and the hyperfine structure constants A(i) for the interstitial V4+ in rutile are theoretically studied from the perturbation formulas of these parameters for a 3d(1) ion in rhombically distorted octahedra. On the basis of the studies, the local axial distortion angle Delta alpha' in the impurity center is found to be about 2 degrees smaller than the host value, characterized as stretching and contraction of the parallel and perpendicular bonding lengths by about 0.28 and 0.14 angstrom,respectively. This results in the less compressed ligand octahedron because of the Jahn-Teller effect and space effect arising from occupation of the impurity V4+ at the interstitial site. The theoretical EPR parameters based on the above local structural parameters of this work are in better agreement with the experimental data than those of the previous studies in the absence of the local angular distortion and the ligand orbital contributions. The two experimental optical absorption bands are also reasonably analyzed.