  We investigate thermodynamics of apparent horizon in the $f(Q)$ universe with
trivial and nontrivial connections. We first explore the perspectives of the
first law, generalized second law and $P-V$ phase transition with trivial
connection. We show that the lowest-order correction of entropy has the same
form as that in loop quantum gravity, and the critical exponents of the phase
transition caused by the lowest-order correction are consistent with those in
mean field theory. We then examine the thermodynamic implication of nontrivial
connections. We find that nontrivial connections in the $f(Q)$ universe imply
non-equilibrium states from the perspective of thermodynamics.
