Abstract: Semiaromatic transparent polyamides with different melt flow rate were synthesized by solid state polycondensation. The effect of water absorption and post treatment on the mechanical properties was studied. It showed that SATPAs water absorption was low, and independent on the molecular weight. The temperature of water and humidity of environment had effects on the water absorption. The higher the temperature of water and the higher air humidity, the faster the SATPA absorbed water. After dipping in the water for 24h, the dimension of the sample didnt change basically. After being treated in water at room and high temperatures, the mechanical properties increase dlittle, on the contrary, elongation at break reduced obviously; after annealing treatment, tensile strength，elongation at break，and notched impact strength all increased.

Key words: semiaromatic transparent polyamide, olid state polycondensation, water absorption property, mechanical property