An LED lamp includes a plurality of LED light units, a connecting member engaged with first ends of the LED light units, a mounting member engaged with second ends of the LED light units, and two strengthening members. The LED light units are juxtaposed together and placed side by side. Each LED light unit comprises a heat sink and a plurality of LED modules engaged with a bottom of the heat sink. The strengthening members extend through two outmost side portions of the LED light units and connecting the connecting member and the mounting member to support the LED light units.