In the present study the identification of phenolics acids and flavonoids compounds from E. gracilis exposed at two copper sulfate (CuSO₄ ) concentrations (0.4 and 3 mM) in the culture medium was evaluated using high-performance liquid chromatography (HPLC). The results showed that E. gracilis treated with 0.4 mM Cu⁺², increased significantly, the total phenolics content (718.86 ± 12.61 µg GA/g) and total flavonoids (361.46 ± 51.93 µg QE/g) with respect to control (137.04 ± 19.80 µg QE/g DW and 669 ± 0.57 µg GA/g DW respectively). However, a non-significant increased of total phenolics content (667.2 ± 6.29 µg GA/g DW) and total flavonoids (150.17 ± 24.23 µg QE/g DW) were observed in E. gracilis exposed to 0.8 mM Cu⁺² with respect to control. The HPLC analysis showed that the exposure of E. gracilis at high doses (0.8 mM Cu⁺²) stimulated the presence of ferulic and chlorogenic acids with respect to control. In contrast, the presence of flavonoids quercetin, and kaempferol were mainly observed in E. gracilis treated with 0.4 mM Cu⁺².  Finally, the present study clearly showed change in the phenolics and flavonoids in E. gracilis exposed to copper. Therefore, the present data could suggest that feluric, chlorogenic acids, quercetin and kaempferol production are involved in Cu⁺² detoxification.