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The effect of pistachio green hull (PGH) at 0, 1.5, 4.5, 13.5 and 27% of the diet on the growth, blood biochemical and hematological parameters of rainbow trout (Oncorhynchus mykiss) of 27.03±0.58 g was investigated in a completely randomized design and in three replications with 14 fish individuals in each. At the end of 8 weeks feeding trial, blood samples were randomly taken from 4 individulas in each replication. Results showed significant differences (p<0.05) in SGR and FCR between 27% treatment and other treatments. No significant differences in Alb, Glo, Tg, GOT (p>0.05) were observed among treatments. Tp (2.76±0.15 g/dl), LDH (2139±44.26 IU/l), ALP (331.9±21.4 IU/l), GPT (407±17.82 IU/l), Hb (8.73±0.7 g/dl) and Hct (33.33±2.28%) had significant differences in group receiving 27% PGH compared with other group (p<0.05). Results showed that high levels of PGH in the diet of rainbow trout had adverse effects on health and growth factors.