BACKGROUND: Shell is one of the most important by-products of shrimp processing methods which can potentially pollute the environment, whereas shrimp shell contain large amounts of chitin and chitosan and can be used as immune and growth stimulator in aquaculture. OBJECTIVES: The purpose of present study was to investigate the effect of oral administration of chitosan extracted from Litopenaeus vannamei's shell on some hematological and growth factors of common carp. METHODS: Shrimp shells were collected from shrimp processing plants and chitosan was extracted. Then 300 common carp were divided into 4 equal groups in 3 trirepcats (12 aquarium totally). Fish were fed with basal food supplemented with 0% (as control group), 0.25% (G2.5), 0.5% (G5) and 1% chitosan (G10) for 60 days. Blood samples were taken every 20 days from each group during the experiment. Samples were used for hematological parameters include: WBC, RBC, PCV, Hb, leukocyte differential count and globular indices (MCV, MCH and MCHC). At the end of study growth indices include: Specific Growth Rate, percentage weight gain and Food Conversion Rate were calculated. RESULTS: The results showed that oral administration of chitosan in different dose didn't affect hematological parameters of Common carp (p>0.05). Meanwhile results indicate that all growth indices improved in G10 compare to control (p<0.05). FCR and SGR in G10 treatment were 2.98±0.64 and 0.60±0.09, versus 3.82±0.30 and 0.44±0.04 in control group, respectively. Lower concentration of chitosan (0.25% and 0.5%) induced no significant change in growth indices of fish (p>0.05). CONCLUSIONS: Although Chitosan extracted from white leg shrimp in concentration of 1% improved growth indices of common carp, no significant impact were seen in hematological parameters. Therefore, 1% chitosan can be used as a growth stimulant in Common carp.