Escuela de Física y Matemática - ESPOCH 1 “DETERMINACIÓN DE RADIACIÓN NATURAL EN LA PROVINCIA DE CHIMBORAZO” Mario Pérez 1 , Wilson López 1 , Dra. Jenny Orbe 1 , Dr. Celso Recalde 1 1 Facultad de Ciencias, ESPOCH, Riobamba. ABSTRACT The natural background radiation exist from the world formation and appears in everywhere such as in the inhaled air, water and ingested food therefore the population are continually exposed to ionizing radiation. The present research determined the natural background radiation in the Chimborazo Province-Ecuador, the exposure and correlation among height and natural background radiation. There were 1300 natural background radiation measures in 130 located points by means of convenience stratified method using a portable Geiger-Müller (GCA-07W) situated to fifty centimeters over the soil. The natural background radiation average found in the Chimborazo Province was 1.42087 mSv/year, showing that this value is lower in 41% to the global average stablished for the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) (2.4 mSv/year). Additionally, it was found a correlation of 0.901536 between height and natural background radiation indicated that the radiation increases to increment the height. Keywords: Natural background radiation, exposure, ionizing radiation, Geiger-Müller detector.