A number of test methods for checking the geometric inaccuracy of the RRTTT type five-axis machining centers have been specified in ISO standards. However such procedures are relatively involved in terms of equipments and operator expertise and simpler means are thus sought. This paper presents a new calibration method to check the geometric inaccuracy of the RRTTT type machining centers which is based on the modified motion of the basic motion described by the spherical interpolation of five axes as specified in clause K6 of ISO 10791- part 6. In addition, a methodology for identifying the static deviations is proposed. This methodology consists of three steps. In the steps 1 and 2, six of ten deviations were identified by means of observation equation. The rest of the ten deviations were identified in the step 3 by means of link geometry of the machining center. The simulations are carried out to verify the proposed calibration method and the results are confirmed that the proposed method gives good results for deviations.