  We present our recent study on baryon-baryon ($BB$) interactions from lattice
QCD with almost physical quark masses corresponding to
$(m_\pi,m_K)\approx(146,525)$ MeV and large volume $(La)^4=(96a)^4\approx$ (8.1
fm)$^4$. In order to perform a comprehensive study of $BB$ interactions based
on lattice QCD calculation with almost physical masses and to make better use
of such large scale computer resources, a large number of $BB$ interactions
from $NN$ to $\Xi\Xi$ are calculated simultaneously. In this report, we focus
on the strangeness $S=-1$ channels of the hyperon interactions by means of HAL
QCD method. The coupled-channel HAL QCD method is briefly outlined. The
snapshots of central and tensor potentials in $^1S_0$ and $^3S_1-^3D_1$
channels are presented for $\Lambda N$, $\Sigma N$ (both the isospin $I=1/2,
3/2$) and their coupled-channel systems.
