A portable collapsible tent includes a cover, a roof frame with a central pole, inclined roof ribs and spreaders, extensible legs, and cross bars. The ribs and spreaders are pivotally and movably jointed at the central pole. A locking unit secures the roof frame when the tent is pitched. Each leg has at one end a fixed corner member that provides a four-way connection and a multi-way support member that movably engages and locks onto the leg to support two cross bars and an inclined rib connected thereto with three diagonal braces. A spring is positioned on the central pole to enable the collapsed tent to be opened easily. A lateral projecting foot member enables each leg to be anchored on the ground. Reinforcement ropes further secure the tent to the ground via the four-way connectors. The portable collapsible tent can be easily set up and collapsed without tools and has a strong structural integrity, able to withstand substantial stress and direct/indirect forces.