European hazelnut has an important place in terms of nutritional and economic value among tree nut species. Because of its nutritional content, the consumption of hazelnuts promotes human health in many ways. These nutritional components are controlled by multiple genes and affected by the environment; therefore, they are quantitative traits. The vast majority of world hazelnut production is provided by Turkey. So it is important to develop hazelnuts with higher nutritional quality for our country. In this work, we aimed to associate genetic diversity data and oil and protein content of hazelnuts to identify QTL. For this purpose oil and protein content were measured in kernels of 96 accessions. Genotypic data were obtained with 30 SSR markers and resulted in 407 polymorphic alleles. According to allelic data, the mean dissimilarity value was 0.52 (52%) for the 96 accessions. Population structure analysis resulted in three clusters with 30, 30, and 16 accessions. Twenty accessions could not be assigned to any cluster and were considered admixed. Association mapping between allelic and phenotypic data indicated that five loci were significantly associated with oil content. The most significant result for oil content belonged to B628-307 loci (p=0.0002, r2=0.145). Three loci were detected for protein content. Among them, A613-153 had the most significant effect (p=0.003, r2= 0.088). We hope that our survey of germplasm and the identified loci associated with oil and protein amount can accelerate hazelnut breeding. In the future this study can contribute to develop new genotypes with enhanced nutritional value.