通过飞行磨测定和扩散观察，研究大头金蝇Chrysomya megacephala (Fabricius)的飞行能力。结果表明：雌、雄虫的平均飞行距离、平均最大飞行速度、平均飞行时间间没有显著的差异。大头金蝇的平均飞行距离25℃时达最高, 为4.478 3 km，之后随着温度的进一步增高而逐渐下降；平均飞行时间20℃时最大，为1.226 2 h；最大飞行速度25℃最大，为1.221 0 m/s。50％，60%，70%和80%相对湿度的平均飞行距离有显著差异，分别为5.747 5，0.791 3，0.385 0 和0.757 5 km；50％RH的平均飞行时间最长为2.786 8 h，平均最大飞行速度中80%RH最高，为2.079 2 m/s。在塑料大棚（长30 m）释放大头金蝇呈扇形扩散，最快速度0.3 m/s，从一端扩散到塑料大棚的另一端所需时间平均为(2.52±0.63)min，最长需要3.08 min，表现出大头金蝇有较强的飞行能力。

The flight capacity of Chrysomya megacephala was surveyed through flight mill and diffusion in plastic chamber. The results showed that the mean accumulated flight distances, the highest velocity and the mean flight time were not significantly different between females and males. The mean flight distance was highest at 25℃, about 4.478 3 km. When the temperature increased from 25℃, the mean flight distance would decrease. The mean flight time was longest at 20℃, about 1.226 2 h. The highest velocity was at 25℃, about 1.2210 m/s. The mean flight distances in relative humidity 50%, 60%, 70% and 80% were 5.747 5 km, 0.791 3 km, 0.385 0 km and 0.757 5 km, respectively. The mean flight time was longest at 50%RH, about 2.7868 h, and the highest velocity was 2.079 2 m/s at 80%RH. The adults of Ch. megacephala released in plastic chamber (30 m×5 m×2 m) diffused in the fan_shaped, and the highest speed was about 0.3 m/s.  The average diffusion time from one end to another was (2.52±0.63) min, with the longest about 3.08 min.