Toxicity of nonlyphenol (NP) one of EDCs was studied with focus on reproduction of the crucian carp, Carassius auratus. Fishes were cultured under control and nonylphnol exposure conditions for 32 weeks. Experimental group was composed of total of 4 groups, 1 control condition and 3 nonylphenol exposure condition ($18;{mu}g;NP;L^{-1},;37;{mu}g;NP;L^{-1};and;83;{mu}g;NP;L^{-1}$). Survival rate was found to be similar in control and $18;{mu};NP;L^{-1}$. However, it is lower In the $37;{mu};NP;L^{-1}$ and $83;{mu};NP;L^{-1}$ in comparison to the control group. Deformation of gonads was the highest in the exposure condition of $18{mu};NP;L^{-1}$ with the female illustrating higher ratio than the male. GSI was not much different in the male but in the female, NP exposure group illustrated lower value compared to the control group. HSI and GI did not illustrate any clear differences between the control and exposure group for both male and female. Intersex was 0% in the wild group, 4.16% in the laboratory control group, and 25.67% in the NP exposure condition with female illustrating higher compared to male. Concentration of blood vitellogenin in female illustrated no clear differences between the control and NP exposure group. However, in the male, it was higher in the NP exposure group in comparison to the control group, and illustrated higher values of vitellogenin compared to the figures found in the female of same con-centration condition.