<p>The olive trees from <i>Olea europaea</i> L. species are cultivated to produce olive oil and table olives. The Chemlal olive cultivar is mainly cultivated in Algeria for oil production. This study aims to investigate the effect of soil pedological parameters (sandy, clay and silt percentage, organic, mineral contents, pH and conductivity) and climatic factors (annual precipitation, and mean temperatures) on olive oil composition including quality traits, oil content and fatty acids profile. The olives were harvested at the same maturity stage from five orchards in the El Bayadh region at the Southwest of Algeria. The oil content was estimated by the Soxhlet method and the fatty acids composition using GC/MS on oils extracted by laboratory oleodoser. Results showed that the five orchards divided in three soil texture types. The oil content doesn’t vary significantly according to the studied soil localities. The fatty acid profiles showed that the oleic acid varied from 66.43 to 73.92% and is the main fatty acid of olive oils from the five localities. Significant differences were noted on some fatty acids as C16:0, C6:1, C18:1, C18:2. Indeed, in these variations, the studied olive oils have good compositions using the International Council Olive Oil limit. Pearson correlation test showed some significant correlations between soil parameters and some olive oil criteria as the NO₃⁻ content that was negatively correlated with free acidity and the phosphorous was positively correlated with pigments contents. The oleic acid doesn’t show any correlations among all soil parameters. Results showed that the BGB orchard on clay loam soil, with an annual rainfall ranging between 124 and 180 mm and a mean temperature of 17&#xa0;°C, seems to be more suitable to olive tree cultivation having olive oils richer in oleic acid (73.92%), lower free acidity (0.36)&#xa0;and peroxide value (9.25 meqO2/kg oil).</p>