In order to improve anti-vibration abilities of an indirect analytic alignment algorithm for SINS, common frequency-domain digital filtering methods was analyzed to estimate anti-vibration abilities as well as their limitations. On the basis, an anti-vibration algorithm without time delay was proposed based on polynomial regression in time-domain, and simulations were conducted to validate its effectiveness compared with the frequency-domain digital filtering methods. The result shows that the polynomial regression method can effectively handle different kinds of vibrations, sudden change of vibration with simple algorithm and no time delay. The anti-vibration algorithm can meet the requirement of fine alignment in short time.