The invention discloses a drainage cistern system for municipal gardens, and relates to the field of drainage systems for municipal gardens. The system is characterized by comprising a cistern body, awater leakage hole is formed in the cistern body, a first slide channel and a second slide channel are formed in the cistern body, sliding assemblies are slidably arranged in the first slide channel,and a first stopping part used for stopping downward movement of the sliding assemblies is arranged in the first slide channel; the sliding assemblies comprise first sliding plates and second slidingplates, and first filtering rope nets are connected to the second sliding plates; starting assemblies used for pushing the second sliding plates are arranged at one side of the second slide channel,and stopping walls used for stopping the starting assemblies are arranged on the first sliding plates; multiple sliding assemblies are arranged, and the first filtering rope nets are connected with multiple second sliding plates and laid in the water leakage hole to prevent foreign matter from passing through the first filtering rope nets. By means of the drainage cistern system, when the first filtering rope nets are clogged, the first filtering rope nets can move towards one side, and a good drainage effect is still maintained even when the first filtering rope nets are clogged.