California wine is wine made in the U.S. state of California, it supplies a vast majority of the American wine production, along with New Mexico wine these American wine regions are longtime examples of viticulture within New World wine. Almost three quarters the size of France, California accounts for nearly 90 percent of production, the production of wine in California is one third larger than that of Australia. If California were a separate country, it would be the world's fourth largest wine producer.