The invention discloses a full-terrain extensible guardrail which comprises a bottom frame, an adjusting device, a stand column and a guardrail take-up device. The bottom frame is arranged on the lower portion to achieve the movement of the guardrail. The adjusting device is arranged on the upper portion of the bottom frame and used for keeping the levelness of the bottom frame, so that the standcolumn at the upper part of the adjusting device is in a vertical state. The guardrail take-up device is installed on the upper portion of the stand column to realize the connection of an extensible belt between two guardrails. The guardrail can realize automatic connection and automatic fencing. The inclination degree of the ground can be detected, and then corresponding adjustments can be performed to guarantee that the stand column is vertical. A supporting block structure is arranged so that the grounding area of the bottom frame can be increased, and the stability is improved.