Elastic modulus is one of the most important indexes to reflect material stiffness. Raining and freeze-thaw lead brick masonry to be in the state of unsaturated water freeze-thaw. The experiment aims to obtain the elastic modulus of ancient bricks under various unsaturated water freeze-thaw. The brick samples were put in the environmental chamber to carry out raining and freeze-thaw action. The experiment including saturated coefficient, saturated degree, dynamic elastic modulus and relative elastic modulus were carried out for these samples. Results show that the dynamic elastic modulus of the samples obviously decreases when saturated degree is equal to or larger than 60%; the elastic modulus of the samples have no significant change when saturated degree is less than 60%, and the samples break when their saturated degree reached a certain value. This paper also discusses parameters like limit saturated degree, which reflect the freeze-thaw resistance for ancient bricks.