On finite volume discretization of interface problems with piecewise constant coefficients Oleg Iliev New finite volume discretizations of interface problems with piecewise constant coefficients are presented and discussed. Standard conditions for continuity of the solution and the normal component of its flux through the interfaces are considered. The cases of continuous and discontinuous right hand side are discussed. The schemes are derived under the assumption that the interfaces are aligned with the finite volumes surfaces. Different schemes are derived under different smoothness assumptions. Second order convergence in $W_2^1$, or pointwise second order convergence is proved for some of the schemes under different smoothness assumptions. Results from numerical experiments are presented in order to demonstrate advanatges of the new schemes.