Abstract： The additional load is one of the most important mechanical performance index of the adaptive base. To research the sensitivity of affecting factors for additional load of the adaptive base, the additional load mechanical model of the adaptive base was established, and the mathematical calculation formula of the additional load was deducted. Besides, the numerical model of the adaptive base was built, the numerical modeling method was verified by the test, and the numerical result was compared with the analytical solution of the additional load. Combining the parametric technology, the multipleinput with the singleoutput neural network method, the sensitivity research for affecting factors of additional load was conducted. The research shows that the minimum diameter D2 in the S bending and the height H from the ground are proportional to the peak value of additional load. The maximum diameter D1 in the S bending, the down bending radius R1 and the upper bending radius R2 of the S bending are inversely proportional to the peak value of additional load. D2, D1 and H are the main affecting factors while R1 and R2 are the secondary affecting factors for the peak value of additional load, and the affecting factors for the additional impact load are D1>H>D2>R2>R1 in order.