[en] In order to evaluate the reactivity coefficients of the TRIGA IAN-R1 core, a simplified core configuration with no control rods and no internal irradiation channels was calculated. The cross-sections set were recalculated running a Wims code for each temperature of fuel, water and the water density. The effective reactivity was calculated using Citation code with a conceptual model and an X-Y-Z calculation in order to avoid buckling recalculations. For the conceptual model of the TRIGA IAN-R1 core, a value of -7.37 pcm/Celcius degrade was obtained for the fuel temperature coefficient; 3.67 pcm/Celsius degrade and -4.28 pcm/Celsius degrade for the temperature coefficient of the moderator and -95.5 pcm/% for the void coefficient.