The acaricidal potential of Ethulia conyzoides L. aerial parts extracts as well as its isolated compounds were investigated against larvae and adults of Tetranychus urticae Koch under laboratory conditions. Chromatographic separation of the extracts gave 3-O-acetyl lupeol, lupan-3-ol, ethuliacoumarin (1) and 7-O-methyl apigenin (Genkwanin), besides a mixture of isoethyliacoumarin A (2), isoethuliacoumarin C (3). The biological evaluation results indicated that ethyl acetate fraction and ethuliacoumarin (1) were the most potent to larvae and adults of Tetranychus urticae. The LC50 values of ethyl acetate fraction were found to be 11.58 and 17.86 ppm, respectively and LC50 values of (1) were found to be 12.72 and 19.22 ppm, respectively after 7 days of treatment.