In this study, different levels of vitamin C (L-ascorbyl-2-polyphosphate) on the hatching efficiency and obtained Artemia nauplii survival were examined at different temperatures. In the first experiment, the effect of different amounts of vitamin C (0, 500, 1000 ppm) on hatching percentage of the Maharloo Lake Artemia cyst was examined with 6 replicates. Results of the first experiment showed that different amounts of vitamin C had no significant effect on hatching percentage. In the second experiment, the effect of different temperatures on the percentage of survival of Artemia nauplii was studied. In this experiment, obtained nauplii from first experiment were put in 3 different temperatures (1, 4, 16 ºC) with 6 replicates for 48 hours, then percentage of survival of Artemia nauplii accounted. Result of the second experiment showed that interaction of vitamin C and different temperatures had no significant on the survival rate of Artemia nauplii. Different amounts of vitamin C (0, 500, 1000 ppm) had no significant difference on the percentage of survival of the Artemia nauplii, but different temperatures had significant effect on survival rate. Results of these experiments showed that increase of the amount of vitamin C had significant difference on hatching percentage of the Maharloo Artemia cyst, no significant effect on survival rate of Artemia nauplii. Also it is found that survival rate of Artemia nauplii in 16 ºC temperatures was more than 1 and 4 ºC temperatures.