Abstract: An adjustable grid having a base with a predetermined width is disclosed. Two ends of the base has a respective fixing portion; each fixing portion having a through hole for being passed through by a rope. Each fixing portion having a clamping device for fixing the rope. By the pulling force of the rope, the base can be installed steadily. The base is pivotally installed with an adjustable grid. A positioning device is installed between the base and the grid for positioning the grid as the grid stands uprightly. Therefore, the users may stumble over the grid and the grid can fall down as it is collided.