Climate changes may cause an increase of precipitation in the Province of Quebec over the next decades. As the performance of flexible pavement structures is closely related to moisture content of soils and aggregates, these structures can be considered vulnerable to climate changes. In order to quantify the effect of future precipitations increase on the pavement service life, this research project was based on a three steps approach: 1) Establishment of a relationship between precipitations and water content in the subgrade layers; 2) Establishment of the relationship between soils water content and soils mechanical properties, quantified with the resilient modulus and the permanent deformation behaviour; 3) Quantification of the effect of increased precipitations on pavement life, based on modification of their mechanical behaviour due to water content increase. For the example considered in this paper, it was found that the service life of pavement structures submitted to future climate may present a service life reaching 0.72 times the service of actual pavement structures. These results vary depending on the soil and damage types considered.