We experimentally investigated the influence of dielectric supports used on RE102 radiated emission tests of the MIL-STD-461F EMC standard for table-top and conductive surface mounted Equipment Under Test (EUT). A variety of dielectric materials which are commonly selected as supports under EUT cables in RE102 tests were investigated by using an actual RE102 test setup in a semi anechoic chamber. Each investigated material yielded different effects on RE102 test results in comparison to the case without support, in other words, with the air support.