What Temperature Do You Cook Meatloaf. Meatloaf can be cooked at 375-400°F in an oven till it reaches an internal temperature of 160°. A large pack of ground meat, about two pounds, takes about one hour fifteen minutes or so.The temperature and time can vary depending on the taste and method of cooking.et it cook in the oven for one and half to two hours. Modify the cooking time depending on the size of the meat loaf. After cooking, let the meat rest for a few minutes before serving. Cut a slice of meat loaf and serve along with the cooked vegetables.