Abstract: The atmospheric refraction environment significantly affects the performance of microwave and ultra-short wave radio equipment, which can reduce or increase the radio horizon of radio equipment in standard atmospheric environment. Taking Rongcheng at the junction of Yellow Sea and Bohai Sea as an example, based on the radiosonde data in 2018, the atmospheric refractive environment parameters of Rongcheng Station are statistically analyzed, including ground refractivity, 1 km refractivity gradient, 100 m refractivity gradient and other parameters. The annual variation range of ground refractivity can reach 100 N units. The annual average ground refractivity is 332. 3 N units. The annual average refractivity gradient of 1 km is -48. 5 N/ km, the annual average refractivity gradient of 100 m is -44. 2 N/ km, the time probability of 100 m refractivity gradient less than -100 N/ km is 3%. Furthermore, the equivalent earth radius factor used for radar horizon calculation and the distribution of radio horizon factor characterizing the expansion or reduction of relative standard atmosphere condition are given. The results show that the maximum equivalent earth radius factor is 4. 5. Compared with standard atmospheric environment, the maximum change of atmospheric refraction environment on radio horizon can reach more than 80%. These results can provide reference for the system design and performance evaluation of the test equipment in the Yellow Sea and Bohai Sea.