Abstract: An apparatus for estimating lipid concentration is provided. According to an example embodiment, the apparatus may include a training data collector configured to collect, as training data, a reference lipid concentration measured through blood samples of a plurality of users for a predetermined time period and sensor data obtained through light signals detected from the plurality of users for the predetermined time period and a processor configured to perform preprocessing including a moving average and data augmentation on the obtained sensor data, select a valid variable relevant to a change in lipid concentration based on the preprocessed sensor data and the reference lipid concentration, and generate a lipid concentration prediction model based on the selected valid variable.