[en] This radiological impacts evaluation covered of radioactivity in water, soil, grass, air samples and ambient gamma radiation that have been carried out in the Kartini reactor area and in the site plan of nuclear power plan are at Ujung Lemah Abang, Jepara, Central Java. The aim of this research was to determine that radiological impacts in the environment around the Kartini reactor compared to natural radioactivity for site plan of nuclear power plan area. The radioactivity in the water, soil and grass samples ware measured by low background beta counting system and were identified by low background gamma spectrometer. The radioactivity in the air samples was measured by beta portable counting system and the ambient gamma radiation was measured by portable high pressurized ionization chamber model RSS-112 Reuther-Stokes. The reactor data measurement was compared to the site plan of nuclear power plant area data for evaluation of radiological impacts on the operating reactor. From the evaluation and comparison can be concluded there are no indication of the radionuclide release from the reactor operation. The average radiactivity in the water, soil grass and air sample from the reactor area were between 0.17 - 0.61 Bq/1; 0,47 - 0,74 Bq/g; 4.43 - 4.60 Bq/g.ash and 49.53 - 70.90 x 10 Bq/cc. The average radioactivity of those sample from the nuclear power plant area were between 0.06-0.90 Bq/I; 0.02-0.86 Bq/g; 1.68-8.07 Bq/g.ash and 65.0-152.3 x 10 Bq/cc. The ambient gamma radiation were between 6.9-36.7 urad/h for the reactor area and 6.8-19.2 urad/h for the nuclear power plant area