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The branching fraction $\mathcal{B}(B^0 \to D^{*-}\tau^+\nu_{\tau})$ is measured relative to that of the normalisation mode $B^0 D^{*-}\pi^+\pi^-\pi^+$ using hadronic $\tau^+ \pi^+\pi^-\pi^+(\pi^0)\bar{\nu}_{\tau}$ decays in proton-proton collision data at a centre-of-mass energy 13 TeV collected by LHCb experiment, corresponding an integrated luminosity 2 fb$^{-1}$. ratio D^{*-}\tau^+\nu_{\tau})/\mathcal{B}(B^0 D^{*-}\pi^+\pi^-\pi^+)= 1.70 \pm 0.10^{+0.11}_{-0.10}$, where first uncertainty statistical and second related systematic effects. Using established fractions for D^{*-} \mu^+\nu_\mu$ modes, lepton universality test, $\mathcal{R}(D^{*-}) \equiv \mathcal{B}(B^0 \mu^+\nu_\mu)$ calculated, $$ \mathcal{R}(D^{*-}) = 0.247 0.015 0.012\, , third due uncertainties on external fractions. This result consistent with Standard Model prediction previous measurements.