The invention discloses a simple nut screening machine. The simple nut screening machine comprises a frame and screen plates. Each screen plate comprises an upper screen plate, a lower screen plate and two connecting plates, a hollow flat cuboid structure is formed by the two connecting plates, the upper screen plate and the lower screen plate, the two ends of a hollow part are provided with a first discharge port and a second discharge port respectively, the height of the first discharge port is lower than the height of the second discharge port. Two risers are arranged in the frame, the frame is divided into a qualified cavity, an undersize cavity, an over-high cavity by the risers, a lead frame is positioned right above the undersize cavity. According to the simple nut screening machine, each screen plate is made in a hollow structure, upper screen holes and lower screen holes are formed in the screen plate, and the first discharge hole and the second discharge hole are formed in the hollow part, so that nuts can be screened accurately and unqualified nuts can be classified, and the subsequent processing is easy and production problems can be found easily.