Glulam timber is currently an interesting solution for building environmentally friendly and mechanically strong structures. However, little is known about the impact of Wetting/Drying (W/D) climatic conditions on glulam durability. This study evaluates the effect of W/D cycles on the bending mechanical properties of glulam. The results of this experimental study show that W/D cycles have significant influence on the bending strength. On the other hand, no significant effect is found on the elastic modulus. The moisture content of specimens is also monitored and the results provide an understanding of the sorption/desorption mechanisms in wood during cycling.