In order to introduce the best strain of Iranian Artemia cyst to larvicultural feeding of aquatic animals, biometrical characteristics of Artemia cysts and newly hatched nauplii of four different geographical regions of Iran (Maharloo Lake, Fars province, Meyqan Lake, Central province Urmia Lake and Fesendooze pond West Azarbaijan province) were determined. Whole cysts and decapsulated cyst diameters, chorion thickness, dry weight and total length of newly hatched nauplii were measured under stereomicroscope equipped with Motic 2000 software MLC – 150C, attached to a monitor. The obtained data were statistically analyzed by one way ANOVA and tested with multivariate Duncan test. The results showed that Artemia urmiana cyst has a significantly larger diameter and nauplius total length than the other cysts (P<0.05) (285.4 ± 0.53 μm and 511.8± 1.27 μm, respectively). Although the chorion thickness of the Meyqan cyst is higher than the others there are not any significant differences between them (P>0.05). The smallest cyst diameter (276.8± 0.58 μm), nauplii total length (491.2±1.17 μm) and consequently the largest number of cysts per gram were obtained from Fesendooz. Due to the suitable size of Artemia samples for shrimp post larvae, ornamental and marine fish larval stage feeding it could be a good candidate for replacing imported expensive cysts.