Experimental tests were conducted to investigate the temperature field within concrete filled steel tube(CFST). The study analyzed the circumferential and radial variations of the temperature field across the component's cross-section over time, under the influence of ambient temperature, solar radiation, and wind speed. The findings revealed notable nonlinearity in the temperature field concerning both time and cross-sectional position. Temperature peaks within the concrete varied in phase with respect to the central measurement point, indicating a discernible phase difference. Radially across the cross-section, temperature changes near the interior exhibited gradual variation, with minimal influence from external environmental factors. The temperature at the central point emerged as a product of various interacting factors, illustrating a degree of complexity. Drawing upon existing temperature gradient models, a temperature gradient formula incorporating multiple parameters such as solar radiation, ambient temperature, and wind speed was established through fitting procedures, and the accuracy of the fitted formula is good.