Ground beef is the meat that is most often used to make meat loaf. Ground pork is often used as well, and ground turkey is an option for those looking to make a healthier version of meat loaf.
Traditionally, meat loaf was made from ground beef chuck, which is an inexpensive cut of meat. Now, it is often made from more expensive, and perhaps more tasty, cuts of beef.
Some meat loaf recipes call for a single kind of ground meat, typically beef, while others use two or more kinds of meat. It is not unusual to find meat loaf recipes that call for beef, pork, and turkey.