Intelligent Heat and Photoelectric Smoke Combined Detector (herein after called as Detector) is consisted of smoke sensing and semi-conductor temperature sensing parts in processing and circuitry. The detector has the advantages of both photoelectric smoke detector and rate of rise and fixed temperature heat detector. Just because of the combination technology of smoke detector and heat detector, it can detect and alarm the combustion of SH (polyurethane plastic fire) and SH (n-heptane fire) in the national standard test. It can also pick up fire with obvious rise of temperature such as alcohol fire, thus extending the application range