NaX zeolite crystals of a uniform particle size of 5 $mu extrm{m}$ were synthesized from seed crystals (2-3$mu extrm{m}$) in a 3-15 wt% mother liquor having a composition 4.12Na2O$.$Al2O3$.$3.5SiO2$.$593H2O In case of the addition 3 wt% of seed crystallization time reduced from 72 hours for without the seed to 24 hours and the yield of NaX zeolite was increased Crystallization of NaX with 15wt% of seed was completed in 12 hours and no other type of zeolite existed. The seeding resulted in an increase in the fraction of large crystals compared with unseeded batches and successfully led to an uniform NaX zeolite crystal. It was postulated that the seeding in the synthesis mixture force the crystal growth to occur immediately without nucleation in the synthesis gel