On a Walker manifold Mf3, we first characterize the Killing vector fields, aiming to obtain the corresponding Killing magnetic curves. When the manifold is endowed with a unitary spacelike vector field ξ, we prove that after a reparameterization, any lightlike curve normal to ξ is a lightlike geodesic. We also show that on Mf3, equipped with a Killing vector field V, any arc length parameterized spacelike or timelike curve, normal to V, is a magnetic trajectory associated to V. We characterize the normal magnetic curves corresponding to some Killing vector fields on Mf3, obtaining their explicit expressions for certain functions f.