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Based on the Gaia DR2 catalogue of hot subdwarf star candidates, weidentified 1587 hot subdwarf stars with spectra in LAMOST DR7. We presentatmospheric parameters for these stars by fitting the LAMOST spectra with {\scTlusty/Synspec} non-LTE synthetic spectra. Combining LAMOST radial velocitiesand Gaia Early Data Release 3 (EDR3) parallaxes and proper motions, we alsopresent the Galactic space positions, velocity vectors, orbital parameters andthe Galactic population memberships of the stars. With our He classificationscheme, we identify four groups of He rich hot subdwarf stars in the $T_{\rmeff}-\log\,g$ and $T_{\rm eff}-\log{(n{\rm He}/n{\rm H})}$ diagrams. We findtwo extreme He-rich groups ($e$He-1 and $e$He-2) for stars with $\log{(n{\rmHe}/n{\rm H})}\geq0$ and two intermediate He-rich groups ($i$He-1 and $i$He-2)for stars with $-1\le\log{(n{\rm He}/n{\rm H})}<0$. We also find that over halfof the stars in Group $e$He-1 are thick disk stars, while over half of thestars in Group $e$He-2 correspond to thin disk stars. The disk populationfractions of Group $i$He-1 are between those of Group $e$He-1 and $e$He-2.Almost all stars in Group $i$He-2 belong to the thin disk. These differencesindicate that the four groups probably have very different origins. Comparisonsbetween hot subdwarf stars in the halo and in the Galactic globular cluster$\omega$ Cen show that only He-deficient stars with $-2.2\le\log{(n{\rmHe}/n{\rm H})}<-1$ have similar fractions. Hot subdwarfs with $\log{(n{\rmHe}/n{\rm H})}\ge 0$ in $\omega$ Cen have no counterparts in the thick disk andhalo populations, but they appear in the thin disk.

Hot subdwarf Atmospheric parameters, Kinematics, and Origins -- Based on 1587 hot subdwarf stars observed in Gaia DR2 and LAMOST DR7