This paper describes the dosimetry characteristic comparison of environmental radiophotoluminescent glass dosemeter (RPLGD) and thermoluminescent dosemeter (TLD) systems employed at the Institute of Nuclear Energy Research (INER, Taiwan). The luminescence centers of TLD disappeared by reading process, and repetition of measurement is impossible. RPLGDs can be repeatedly read and keep the luminescence centers for a long time. The RPLGD fading is about 1% within 30 days after being exposed to ionizing radiation. Environmental cumulative doses measured by a RPLGD and a TLD were compared at the same monitoring points of INER during two years. The sensitivity of TLD decreased with gradual loss due to fading at higher temperatures. The difference between results obtained by RPLGD and TLD is discussed mainly with respect to the dependence on the ambient temperature. In addition, this research also refers to the American National Standard Institute (ANSI) Draft Standard N13.29 (1996) to organize the environmental dosimetry performance tests of the INER's RPLGDs and the TLDs. The results mean that both kinds of dosemeters can meet the performance test criteria. An accreditation procedure for the institutes which provide the environmental dosimetry services in Taiwan was suggested based on the comparison results of these two dosimetry systems.