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Microalgae <i>Dunaliella salina</i> contains useful molecules such as &#946;-carotene and fatty acids (FAs), which are considered high value-added compounds. To extract these molecules, supercritical carbon dioxide was used at different operative conditions. The effects of mechanical pre-treatment (grinding speed at 0&#8315;600 rpm; pre-treatment time of 2.5&#8315;7.5 min) and operating parameters for extraction, such as biomass loading (2.45 and 7.53 g), pressure (100&#8315;550 bars), temperature (50&#8315;75 &#176;C) and CO₂ flow rate (7.24 and 14.48 g/min) by varying the extraction times (30&#8315;110 min) were evaluated. Results showed that the maximum cumulative recovery (25.48%) of &#946;-carotene was achieved at 400 bars and 65 &#176;C with a CO₂ flow rate of 14.48 g/min, while the highest purity for stage (55.40%) was attained at 550 bars and 65 &#176;C with a CO₂ flow rate of 14.48 g/min. The maximum recovery of FAs, equal to 8.47 mg/g, was achieved at 550 bars and 75 &#176;C with a CO₂ flow rate of 14.48 g/min. Moreover, the lowest biomass loading (2.45 g) and the first extraction cycle (30 min) allowed the maximum extraction of &#946;-carotene and FAs.