This study aims to improve the aceuraey of radiosity measurement. The study uses a custommaderadiation source and a radiation receiving device to explore the relationship between radiosity and itsinfluencing faetors.The radiosity of objeets inereases with roughness and is influeneed by surfaee color. Theradiation output of an object is proportional to the fourth power of its the rmodynamic temperature and inverselproportional to the square of its distance. The maximum error of the experimental results is only 0.002 48 , withother errors being less than 10~4.The goodness of fit is as high as 0.999 89, close to l, indicating that the method is highly aecurate. 'This study is significant for aecurate temperature measurement, material property characterization ,the rmal engineering process optimization , and environmental thermal radiation monitoring.