Is it safe to eat cooked refrigerated roast beef after 10 days?

It is not safe to eat cooked refrigerated roast beef after 10 days. According to the USDA Food Safety and Inspection Service, cooked leftovers should be discarded after 3 to 4 days in the refrigerator. After that, the risk of foodborne illness increases. Listeria is a bacterium that can grow at refrigeration temperatures, so it can be a particular risk with cooked meats, as well as some dairy products.