The invention discloses a lamp with adjustable wattage, which comprises a lamp, lamp filaments and an adjustable switch, wherein the lamp filaments have different wattage and are connected with a plurality of groups of wires in the lamp, and the adjustable switch is connected with a plurality of groups of lamp filaments. The lamp can be any lamp made of various materials and adopts direct current or alternating current. The filaments which have different wattage, are connected with a plurality of groups of wires in the lamp and used for preventing independence and are made of wolfram filaments are arranged in the lamp. The lamp filaments with different wattage can be used according to needs. The adjustable switch is connected with the plurality of groups of lamp filaments through the wires and used for adjusting and controlling the lamp filaments at the upper end of the lamp. The adjustable switch can be adjusted according to needs to achieve the purpose of converting the lamp filaments with different wattage. One end of the adjustable switch can be in contact with or connected with a power source. The lamp with adjustable wattage can be used in different wattage, thus the luminance brightness is adjusted, and the electric energy is saved.