We report the first high-significance GeV gamma-ray detections of supernova remnants HESS J1731-347 and SN 1006, both of which have been previously detected by imaging atmospheric Cherenkov Telescopes above 1 TeV. Using 8 years of Fermi Pass 8 data at energies between 1 GeV and 2 TeV, we detect emission at the position of HESS J1731-347 with a significance of $sim 5sigma$ and a spectral index of $Gamma = 1.66 pm 0.16_{rm stat} pm 0.12_{rm syst}$. The hardness of the index and the good connection with the TeV spectrum of HESS J1731-347 support an association between the two sources. We also confirm the detection of SN 1006 at $sim 6sigma$ with a spectral index of $Gamma = 1.79 pm 0.17_{rm stat} pm 0.27_{rm syst}$. The northeast (NE) and southwest (SW) limbs of SN 1006 were also fit separately, resulting in the detection of the NE region ($Gamma = 1.47 pm 0.26_{rm stat}$) and the non-detection of the SW region. The significance of different spectral components for the two limbs is $3.6sigma$, providing first indications of an asymmetry in the GeV $gamma$-ray emission.
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