Abstract: Acalypha hispida (Burm.) F. flowers (Euphorbiaceae) were subjected to distillation using a hydro-distiller (all-glass Clavenger apparatus) to extract the essential oil present in the plant samples. GC and GC/MS analysis were carried out on the essential oil and was found to contain 44 compounds constituting 99.98% of the total oil composition. The compounds were identified by spectral comparison to be mainly alcohols, esters, ketones, terpenes and hydrocarbons. The principal constituents are 15, 16-Epoxylabda-13 (16), 14-dien-8α-ol (12.75%), 8, 14-Cedranoxide (12.19%), Curcumene (10.14%), 1-Hexandecene (8.37%) and Ethyl vanillin (6.87%) while others were present in trace amounts. Brine shrimp lethality assay was carried out using brine shrimps at 10, 100 and 1000 ppm to determine the toxicity of the oils to living organisms (shrimps). LC50 value (μg mL-1) of 4.3715 obtained showed that the essential oil of A. hispida flower is toxic. The antioxidant properties of essential oils of A. hispida flowers were investigated using the UV/Visible spectrophotometer. The oil exhibited weak activity as a radical scavenger in the experiment using 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH), indicating that A. hispida oil has very weak ability to donate hydrogen when compared with the standard Butylatedhydroxylanisole (BHA). The absorption is stoichiometric with respect to the number of electron taken up. At 20 μg mL-1, the oil activity was 0.9360±0.037 (26.5% inhibition) which was less than that of BHA (70.2%).