There are lymph nodes throughout your body. One happens to be in front of your ear and is called the pre-auricular lymph node. The pre-auricular lymph nodes can become swollen due to infection, autoimmune diseases, and cancer. As with all swollen lymph nodes, the nature of the swelling is important in distinguishing the urgency of the situation. For nodes that are soft, easy to move under the skin, painful, and/or obviously inflamed, that's likely caused by an infection that has spread. This requires treatment, of course, but is not as serious as if the node is hard (like a marble) and fixed under the skin. Such a node needs to be checked out by a doctor within the next few days.