  We discuss black hole solutions of Einstein gravity in presence of nonlinear
electrodynamics in dS spacetime. Considering prescribed entropy, thermodynamic
volume of dS spacetime, We investigate properties of the effective
thermodynamic quantities under influence of nonlinearity parameter $\alpha$.
They show a similar phase transition and criticality properties with that of
black holes in AdS spacetime. And the nonlinearity parameter $\alpha$ combined
with electric charge is found to have effects on the phase structure. By the
Ehrenfest equations we prove the critical phase transition is a second order
equilibrium transition.
