Nonylphenol (NP) is a widely used industrial chemical that exists heavily in the aquatic environment and it is considered a severe contaminant in the ecosystem. Evidence of the severe effects of NPs on different aquatic organisms exists in a number of axes which may be estrogenic and non-estrogenic. In this study, we report the effect of NP on zebrafish (Danio rerio) embryos. One hour post fertilized (hpf) eggs were exposed to graded levels of NP (0.01, 0.03, 0.1, 0.3, 1, 3 and 10 μM), ranging from lower more environmentally relevant levels to high lethal levels. The embryos/larvae were checked at 24, 48 and 72 hpf to study the development and survival rates. Morphological abnormalities in different organs were photographed and examined. Embryos were highly affected by NP in a dose-dependent pattern. Through a comparative approach of the treated embryos with the control group, it could be revealed that 0.01, 0.03, 0.1 and 0.3 μM have no side effect on the embryos, meanwhile 1 and 3 μM caused severe oedema and less development, moreover 10 μM was lethal from the beginning. The results of the current study show that more attention should be given to assess the risk of these compounds in the aquatic environment.