The theme of the diploma thesis was to found out the temperature effect on magnetic properties of low coercive magnets Sm2Co17. Sintered samples and two-stage temperature profile were obtained in company Magneti Ljubljana d. d. Samples were divided into seven series, which were treated with two-stage heat treatment at different temperatures. The temperature between the individual samples rose by 5 °C, so the temperature of the two-stage treatment in the sample from Serie 1 was 780 °C/800 °C, and 800 °C/820 °C for the sample from Serie 7. The samples were heated from room temperature 20 °C to 780 °C (for Serie 1), where they were kept for 1h, followed by cooling to a temperature of 400 °C, with a cooling rate of 1 °C/min, and then rapid cooled back to 20 °C. The second part of the heat treatment started with heating from 20 °C to 800 °C (for Serie 1), the samples were once again kept at this temperature for 1h and then cooled to a temperature of 400 °C at a cooling rate of 1 °C/min, where they were finally cooled back to 20 °C. After the heat treatment we measured the demagnetization curves on all of the samples. On samples from Series 1 [780 °C/800 °C], Series 4 [795 °C/805 °C] and Series 7 [810 °C/830 °C] we made additional measurements on X-ray powder diffraction aparature (XRD), Scanning electron microscope (SEM), metallographic analysis and grain size analysis. By using these investigative methods, we tried to determine why the coercivity of the Sm2Co17 magnets increased due to the increase in the temperature of the heat treatment profile. From the results of the analyses, we found out that no new phase is obtained in the investigated temperature range, nor does the proportion of phases change and the size of crystalline grains remained unchanged regardless to the temperature level.