It is conjectured since long that for any convex body $P\subset \mathbb{R}^n$ there exists a point in its interior which belongs to at least $2n$ normals from different points on the boundary of $P$. The conjecture is proven for $n=2,3,4$. We treat the same problem for convex polytopes in $\mathbb{R}^3$ and prove that each generic simple polytope has a point in its interior with $10$ normals to the boundary. This is an exact bound: there exists a tetrahedron with no more than $10$ normals from a point in its interior.