The invention discloses an embedded type harmful gas detection system, which comprises a cylinder, a reaction gas chamber; a gas pump, a flow sensor, an illuminating apparatus, an image acquisition instrument, an embedded type ARM9 chip, a lower computer PIC16F877, a touch screen, a porphyrin array sensor, a temperature sensor, a humidity sensor and a controllable heater, wherein the cylinder is used for storing a gas to be detected; the gas pump and the flow sensor are connected in series between the cylinder and the reaction gas chamber; the illuminating apparatus is arranged at the bottom of the reaction gas chamber; the image acquisition instrument is arranged at the top part of the reaction gas chamber; the embedded type ARM9 chip is connected with the lower computer PIC16F877 through an RS232 serial port; the touch screen is connected to the embedded type ARM9 chip; and the porphyrin array sensor, the temperature sensor, the humidity sensor and the controllable heater are arranged in the reaction gas chamber. By using a principle that different color reactions appear when the porphyrin array sensor contacts the gas, and extracting, processing, performing match identification on spectral information, the system finally obtains information on the gas to be detected, displays the information and gives an early warning in time, so the system is suitable for detecting toxic, harmful and volatile organic gasses in the fields of industrial operations, chemical industry, foods, environmental protection, interior decoration, safety and the like.