Foldable Bag

A foldable bag made of a flexible material, comprising:

• a bottom wall;
• two side walls connected to two opposite sides of said bottom wall respectively;
• and
• two connecting walls respectively connected with said two side walls and said bottom wall to define a containing space therein;
• wherein each of said side walls has a first fold line which is parallel to said bottom wall and capable of being folded towards a center of said foldable bag;
• wherein each of said connecting walls has two second fold lines and a third fold line, said two second fold lines extending and intersecting along two diagonal lines of said respective connecting wall and said third fold line extending through an intersection point of said two second lines and in parallel to said bottom wall while two ends of said third fold line are respectively connected to respective ends of said two first fold lines and said second fold lines and said third fold lines are capable of being folded toward a center said foldable bag.