Individual sugars, organic acids, anthocyanins and vitamin C were quantified in strawberry fruits of four newly-bred cultivars grown at two production sites in Switzerland with different soil, climatic conditions and altitudes (1060 and 480 m above sea level). All the measured compounds were significantly influenced by genotype. Pelargonidin-3-glucoside was the main anthocyanin present in all cultivars, while the presence of other pelargonidin derivatives was genotype-dependent. Differences of about 2-fold were observed among the studied cultivars for their vitamin C content. In the mountain region, where plants produced a higher fruit yield over a shorter period, the concentration of both health and taste-related compounds was detrimentally affected. In particular, the vitamin C content in the fruits was negatively related to the average yield per day. However, the compositional variations of strawberry fruits in response to different production sites were genotype specific. Within the four cultivars studied, cv. Antea was most affected by the production site, showing generally lower contents of all analysed compounds when cultivated at higher altitudes, whereas cv. Clery seemed to have the more consistent chemical composition, regardless of production site. The results presented in this work corroborate the dominant role of strawberry genotype over environmental factors.