This study intended to investigate the durability of recycled needle punched natural jute fiber mats with 32 Vol.% fiber volume reinforced unsaturated polyester matrix composites by investigating water absorption and thickness swelling under the effect of hot water absorption at 100oC for 96, 192, 384 h immersion times compared to the virgin specimens. Moreover, the effect of drying of these immersed composites for 6 h at 100oC in a drying oven for different immersion times was investigated. The results showed that as the immersion time of the composites increases, the water absorbed by the composites increases and so the thickness swelling increases. On the other hand, when the immersed specimens are dried for 6 hours, the water absorption of the composites decrease compared to those of the immersed specimens and therefore the thickness swelling of the composites decreases after the specimens are dried compared to those of the immersed specimens.