A multimedia data recording apparatus is disclosed that enables large-volume recorded data to be recorded for a long period in accordance with the importance of the data, by means of a simple configuration and simple processing, and without imposing a heavy load on the system. In this apparatus, a layer classification section classifies video data captured by a surveillance camera and input via a video processing section into a plurality of layers on a frame-by-frame basis according to importance. A data recording section assigns a file to each layer and records classified data in a data recording medium. If an information amount reduction section detects that the vacant capacity of the data recording medium has reached or fallen below a threshold value, it deletes a frame belonging to the lowest layer among the plurality of layers.