A kind of multimedia monitor system used in residential area for theft-proof and fireproof is developed.Pyroelectric infraredsensor and ionic smoke sensor are applied in detection of theft and fire respectively.VAjetS1500-SA encoder,LAN and VAjetS1500-RA decoder are made to collect,transfer and display pictures .The center processor is a Motorola 68860 CPU.The signals of pictures and sound are processed in accordance with MPEG4.