Olax psittacorum (Lam.) Vahl. has versatile ethnopharmacological healing property in addition with incomplete research are adequate pieces of information to support the choice of the plant to build up proper data in acute and sub-chronic toxicological, cytotoxicity with ex vivo and in vivo antioxidant profile as well as qualitative analytical illustration through GC–MS of the selected extracts obtained from different parts of the plant. We have extracted leaf methanolic extract (LME), stem methanolic extract (SME), stem aqueous extract (SAE) and fruits aqueous extract (FrAE) for the above mentioned respective studies. OECD guideline 420 and 407, brine shrimp lethality (BSLA), lipid peroxidation, catalase assay was conducted to gather information on toxicity, cytotoxicity, and antioxidant properties respectively. BSLA study indicates that LME may be a good choice to develop as an anticancer drug for future perspective ( LC50 = 41.88 μg/ml). Both LME and SME have been selected for ex vivo and in vivo antioxidant analysis on the basis of their low toxicity and GCMS analysis. Moreover, in vivo lipidperoxidation as well as catalase assay both having significant difference (P < 0.05) between the groups except LME 200 and positive control (P = 0.084) as well as LME 200 and SME 100 (P = 0.054) respectively. This study justifies that high dose exposure of FrAE, SAE, and SME could be so toxic due to changes in biochemical parameters and in comparison, LME is safer according to the significant (P < 0.05) outcome statistically. LME and SME are safe to consume at a dose of ≤ 200 mg/kg/bw as herbal supplements with antioxidant property.