  In this paper, we prove existence and orbital stability results of periodic
standing waves for the cubic-quintic nonlinear Schr\"odinger equation. We use
the implicit function theorem to construct a smooth curve of explicit periodic
waves with \textit{dnoidal} profile and such construction can be used to prove
that the associated period map is strictly increasing in terms of the energy
levels. The monotonicity is also useful to obtain the behaviour of the
non-positive spectrum for the associated linearized operator around the wave.
Concerning the stability, we prove that the dnoidal waves are orbitally stable
in the energy space restricted to the even functions.
