Understanding of the pathogenesis of obesity changed with the development of medicine. In this article it was considered the calcium metabolism in this pathology, since poorly understood nutritional impact of obesity on metabolic processes in bone tissue, that caused the relevance of this study. Therefore, the aim of this investigation was to determine the level of calcium, magnesium and zinc in dental hard tissues and to establish their relationship with body mass index of animals in case of diet-induced obesity. It was investigated the calcium, magnesium and zinc level in dental hard tissues of nonlinear white rats in case of alimentary obesity using the atomic absorption spectrophotometer. The experimental model of alimentary obesity reproduced by applying inductor of food craving - sodium salt of glutamic acid in a ratio of 0,6: 100,0 and high-calorie diet. It was found that body weight of rats with alimentary obesity in 28 days observation exceeded by 52,8% the rate in the animals with a standard diet (p<0,05). The study of macro and trace element composition of dental hard tissues showed the decrease their level within 14 days of observation, including calcium decreased by 6,8% magnesium - by 58,1% and zinc - by 40,5% compared with control (p<0,05). After 28 days it was decreased the content of basic bioelements of hard dental tissues in diet-induced obesity: calcium by 28,3 %, magnesium – by 79,8 % and zinc – by 53,8 %, compared to the data of the results after 14 days (p<0,05). In general, during the observation bioelements content in hard dental tissues decreased as follows: calcium – 1,5 times, magnesium – 11,8 times and zinc – 3,6 times (p<0,05). For the comparison of changes in the content of bioelements in dental hard tissues of experimental diet-induced obesity we equated to 100% the control group. Analyzing the dynamics of trace elements changes, most interesting was magnesium level, which decreased most significant. It was found negative correlation between body mass index of animals and magnesium level (r = (-0,50); p<0,05) 28 days after the start of the experiment. Therefore, in case of diet-induced obesity in rats the amount of main bioelements in the hard tissue of teeth are decrease: 1,5 times - the calcium, magnesium - 11.8 times and zinc - 3.6 times (p<0,05), while magnesium plays the role of reducing bone mineralization factor during the overweight.