The invention discloses a water permeable 
brick and a preparation method thereof. The water permeable 
brick comprises two parts, namely a 
surface layer and a base layer, wherein the material of the 
surface layer is prepared from the following components in percentage by 
mass: 60-70% of 
ceramic sand, 15-20% of sand and 15-20% of 
cement, and in addition to the 
solid components with the sum of 100% in percentage by 
mass, water accounting for 50-60% by 
mass of 
cement is further added; and the material of the base layer is prepared from the following components in percentage by mass: 45-65% of building 
silt unburned ceramsite, 10-15% of 
cement, 5-10% of 
fly ash, 10-15% of 
melon seed-shaped 
drug slices and 10-15% of sand, and in addition to the 
solid components with the sum of 100% in percentage by mass, the water accounting for 30-40% and a 
water reducer accounting for 1-1.5% relative to total mass of the cement and the 
fly ash are further added. The water permeable 
brick disclosed by the invention is prepared by using the building 
silt unburned ceramsite to replace natural aggregate or calcined ceramsite, on one hand, the using ways of the building 
silt unburned ceramsite can be expanded, the 
utilization rate of 
solid wastes is improved, and negative effects on an environment are reduced, and on the other hand, the obtained water permeable brick has excellent performance.