Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate (SAPO) microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer (PSA) and scanning electron microscope (SEM). The PSA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. Student t-test and variance ratio test (F-test) methods were performed for the significance of results by the analysis of variance (ANONA) and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett & Teller (BET) volumetric technique and v-as plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials. A particle size and particle size distribution using particle size analyzer (PSA) and scanning The results of these techniques for estimation of particle size were compared and correlated statistically. Student t-test and variance ratio test (F-test) methods were performed For the significance of results by the analysis of variance (ANONA) and multiple-range tests. Textural and surface characteristics of as evaluated by Brunauer, Emmett & Teller (BET) volumetric technique and v-as plotting method. surface area and micropore volume of microporous materials were higher than those of the h igh siliceous zeolites and its zeotype materials.