This disclosure is directed to an electric support rod having a driving assembly, an actuating assembly, and a bearing. The driving assembly has a first outer tube and a driving unit in the first outer tube. An internal thread is configured in the first outer tube. The actuating assembly has a second outer tube and a transmission screw rod in the second outer tube. Multiple elastic arms axially are extended from the second outer tube and arranged spacedly around the transmission screw rod. Each elastic arm has an outer thread structure and a hook portion. The second outer tube is inserted in the first outer tube, the internal thread is screwed with the outer thread structure. One end of the transmission screw rod protrudes from the second outer tube to engage the driving unit. The bearing sheathes the transmission screw rod and the hook portion latches the bearing.