The near-surface seismic technique involves refraction, reflection, borehole, and surface-wave methods. The seismic wave velocity and porosity can be estimated whit a compound method to increase the subsurface observations resolution. The porosity is an essential parameter controlling the compressibility, relative density, and natural state of the soil. So, here, we compared porosity estimation theories, including Wood, Gassmann, and Foti. The results indicated due to compressional and shear velocity values measured for depths less than 20 m, the calculated porosity using the Gassmann method shows the highest agreement with real values, whereas utilizing the Wood method shows a difference between the values with high dispersion. Also, compressional wave velocity, the bulk modulus of fluids, and soil density are the most effective parameters affected porosity estimation. In contrast, the shear wave velocity has the least effect on it. By adding the limiting conditions, the estimated porosity of all three theories is reliable