Equations expressing electromagnetic fields in the core, first and second cladding regions of W profile optical fiber in terms of eight constants will be presented. These constants will be determined by applying the boundary condition that the tangential components of electric and magnetic field must be continuous across the core - first cladding and first cladding - second cladding interfaces. By requiring the continuity of appropriate tangential components set of eight homogeneous equations will be obtained. These equations have nontrivial solution only if determinant of the coefficient matrix vanishes. This condition leads to the compact eigenvalue equation of the W profile optical fiber.