The WTO Appellate Body largely upheld a panel ruling last October that India's import restrictions were not based on international scientific standards on animal health and were discriminatory.
US officials said the win will help lower trade barriers and open new markets for US farmers.
"I welcome this win, which will help us eliminate unjustified trade barriers so US farmers can sell high quality US agricultural products to customers around the world," US Trade Representative Michael Froman said in a statement.
The United States brought the case in March 2012. The most recent outbreak of high pathogenic avian flu in the United States was in 2004. Since then India has had over 90 such outbreaks, according to the USTR.
“This is a major win for US agriculture and, in particular, the US poultry industry," US Secretary of Agriculture Tom Vilsack said.
Win helps open markets
"I welcome this win, which will help us eliminate unjustified trade barriers so US farmers can sell high quality US agricultural products to customers around the world," US Trade Representative Michael Froman said in a statement.