  Homes' law, $\rho_{s} = C \, \sigma_{DC} \, T_{c}$, is a universal relation
of superconductors between the superfluid density $\rho_{s}$ at zero
temperature, the critical temperature $T_{c}$ and the electric DC conductivity
$\sigma_{DC}$ at $T_c$. Experimentally, Homes' law is observed in high $T_c$
superconductors with linear-$T$ resistivity in the normal phase, giving a
material independent universal constant $C$. By using holographic models
related to the Gubser-Rocha model, we investigate how Homes' law can be
realized together with linear-$T$ resistivity in the presence of momentum
relaxation. We find that strong momentum relaxation plays an important role to
exhibit Homes' law with linear-$T$ resistivity.
