The invention discloses a shielding device for geological radar low frequency unshielded antennas. The shielding device comprises a shielding body, a net bag and a support frame. The support frame comprises telescopic rods and clamp hooks. After the two telescopic rods are stretched, the telescopic rods are clamped by a plurality of clamp hooks to form the support frame. The net bag is set in theshielding body, is placed on an electronic unit and is connected with the support frame through utilization of hooks, thereby limiting movement of the shielding body. The shielding body is set on thesupport frame and is used for wrapping the electronic unit and the antennas. According to the structure, reflected waves and radio frequency interference (RFI) from the air can be shielded, vibrationsignals possibly generated in the shielding body can be absorbed, and data collection is prevented from being influenced by vibration generated between the shielding body and the antennas.