Bush, a potential Republican presidential candidate, spoke at the Road to the Majority Conference sponsored by the Faith and Freedom Coalition, The Washington Post reported.
"Immigrants create far more businesses than native-born Americans," he said. "Immigrants are more fertile, and they love families, and they have more intact families, and they bring a younger population. Immigrants create an engine of economic prosperity."
Bush, whose wife was born in Mexico, said China, Japan and European countries do not have a tradition of welcoming immigrants. He is a long-time advocate of immigration reform.
"If we don't do it, we will be in decline, because the productivity of this country is dependent upon young people that are equipped to be able to work hard," Bush said.
The Republican Party lost the 2012 presidential election partly because of Mitt Romney's poor performance among Hispanic voters. But many speakers at the conference, like Rep. Michelle Bachmann, R-Minn., continued to take a hard line on immigration.