Abstract: A semi-microscopic proton optical potential with parameters is constructed for analyzing elastic scattering data.It's real part is given by a folding model incorporated with one-body density matrix of shell model with Woods-Saxon potential,and the imaginary part is taken consistently with that of Koning-Delaroche(K-D) global optical potential.Potential parameters are obtained by fitting proton elastic scattering data up to 200 MeV in a range of mass number A=28~90.Compared with measurements of elastic scattering angular distributions and analyzing powers it is overall better than those of K-D global optical potential.