This study aimed to examine the accumulation of oil, fatty acids, sterols and tocopherols contents and compositions during fruit development on the new cultivar of Chia Oruro (Panam Cie, France) cultivated in France. This cultivar is the first released genotype in Europe and for cultivation in Europe. The experiment was conducted in 2017, in south-western France at the Regional centre for organic agriculture, at Auch (near Toulouse, South-West of France). Four samplings were made at 17, 24, 27 and 35 days after flowering (DAF). These dates of sampling correspond to stages 7–8 (fruit development and maturity) of BBCH scale. Oil content, fatty acid composition and sterols and tocopherols contents and profiles were determined. The highest levels of oil and tocopherols were reached at 27 DAF. In contrast, phytosterols content was highest at 17 DAF (726.2 mg/100 g of oil) and decreased after this date. β-sitosterol was the main sterol in chia seed (63.4 to 89.1% of total sterols, depending of stage of fruit development). γ-tocopherol represented more than 92% of the total tocopherols present in the seed. High levels of polyunsaturated fatty acids (74.4 to 80% of total fatty acids) were observed in our study confirming those already reported in this species. High levels of saturated and monounsaturated fatty acids were reported at earlier stages and decreased gradually during fruit development. Polyunsaturated fatty acids followed an opposite trend. Their level was lowest at 17 DAF (74.4%) and increased gradually to reach their higher level at 35 DAF (80%). These results suggested clearly the interest to harvest and use of seed before entire maturity of the grain.