The invention discloses a sandy saline and alkaline land soil remediation device. The sandy saline and alkaline land soil remediation device comprises a water storage sponge, a bottom plate, a water suction sponge, a shell and a top plate. A separation plate is arranged at the top end in the shell, and a plurality of mounting holes are evenly formed in the separation plate and the bottom of the shell at equal intervals. According to the sandy saline and alkaline land soil remediation device, the water suction sponge is arranged at the position, between an upper pressing plate and a lower pressing plate, in the shell, the water storage sponge is arranged at the position, above the separation plate in the shell, plants are planted on soil above the shell, the water suction sponge can be utilized for absorbing and draining underground water on the deep layer of the soil, it is avoided that underground water where salt is dissolved rises to the surface of the soil through the capillary action to evaporate to form saline and alkaline land, rainwater permeating into the shell can be collected, the interior of the shell and a drainage can be collected, and the service life of the device is prolonged. The wettability of the soil is improved through the water storage sponge arranged above the separation plate, growth of the planting is convenient, the soil on the upper layer is managedand remediated, and therefore the effect and efficiency of saline and alkaline land management are improved.