Diagnostics by HPLC proved that the Populuseuphraticaplant growing on the banks of the Tigris River in the regions of Mosul and Tikrit contained a number of phenolic compounds, which included: hydrobenzoic acid, gallic acid, sacid, rutin, apigenin, ferulic acid, kaempferol, and sennapic.Andthe results showed that the phenolic compounds of the leaves of Populuseuphratica (Tikrit - Mosul) were identical in their presence and appearance in both plants, with a superiority in the total concentration of the phenolic compounds of Populuseuphratica growing in Tikrit over the same plant growing in the city of Mosul with a concentration of (3.35 and 2.367) mg. /gm and respectively.The results indicated that the use of phenolic compounds and crude petroleum ether and alcoholic extracts of the study plant as antioxidants at different concentrations, and comparing them with ascorbic acid as a standard sample, all of which led to sniping of the DPPH free radical; The highest sniping percentage of the phenolic compounds of the Euphrates/Tikrit and Mosul plants was (95.7% and 90.2%), respectively, at a concentration of 500 μg/ml, superior in proportion to all other products, as well as superior to the standard sample, whose sniping percentage of free radicals was (85.6%). And at the same concentration, and that the inhibition of free radicals increases with the escalation of the concentration of the natural active compounds of the plant.