Background and Objective: Pregnancy is a special physiological condition. Administration of some drugs during pregnancy may cause harm to the embryos. Congenital defects are physical deformities that affect one or more organs. The aim of this study was to demonstrate the effect of different doses of meloxicam on different stages of chick embryo development. Materials and Methods: One hundred chicken eggs were incubated at 37.8±0.1°C and 65-75% humidity. The eggs were divided into 8 groups (each set contained 12 egg): Six groups were administered meloxicam in increasing doses (0.001 mg/0.1 mL, 0.01 mg/0.1 mL and 0.02 mg/0.1 mL) post 2 days and 6 days of incubation respectively and the two rest groups represented the control groups. All of the embryos were extracted from the eggs after 48 hrs of injection for morphological and quantitative studies. Results: The results of the current study on different stages of chicken embryo development demonstrated that application of meloxicam in high doses caused weakly or absence of vitelline vascularization. The high doses of meloxicam caused embryonic malformations such as subcutaneous haemorrhage, absorbed embryos, reduced fore and hind limb, very thin skin and exencephaly. The percentage of dead embryos of groups was injected with meloxicam post 2 and 6 days of incubation was 53.13 and 42.43, respectively. A significant decrease was noted in the length and weights of treated groups post 6 days of incubation. Conclusion: The results revealed that the administration of meloxicam in high doses caused weak or absence of vitelline vascularization, growth retardation to embryos and many congenital malformations. Further studies needed to determine the safety of meloxicam in therapeutic doses.