A huge amount of building waste was caused by collapsed houses and dilapidated buildings as a result of Wenchuan earthquake. The smooth disposal of building waste will make the post earthquake reconstruction work effective. Based on the statistics of the earthquake damage and the relationship between different building structures and building waste produced, it was indicated that masonry structures, frame structures and mixed structures between them are the main source of building waste. An initial mathematical model about the amount of building waste in the disaster area was firstly set up, then the type and the quantity of building waste were statistically analyzed from the aspects of structure,materials and damage situation. Finally, the composition and distribution characteristics of building waste in disaster area were concluded as:the main building waste is waste concrete and waste brick, and most of it comes from the masonry structures.
