This utility model relates to the field of writing tablet technology and discloses a foldable portable writing tablet, including a first writing tablet and a second writing tablet disposed below the first writing tablet. Folding components are disposed on the inner walls of the first and second writing tablets. A limiting component is disposed on the upper surface of the first writing tablet. The folding component includes a hinge disposed on the inner walls of the first and second writing tablets. A connecting rod is fixedly connected to the outer wall of the first writing tablet, and a limiting groove is formed in the inner wall of the connecting rod. A connecting box is fixedly connected to the outer wall of the second writing tablet, and a button is slidably connected to the inner wall of the connecting box. In this utility model, the two writing tablets are connected by a hinge. Pressing the button moves the relevant components, causing the limiting block to disengage from the limiting groove and complete the folding. Releasing the button pushes the limiting block back to its original position, achieving convenient folding and storage, reducing space occupation, and improving portability.