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Based on the distribution of long-period Cepheids, we have redetermined theorientation parameters of their principal plane in the Galaxy. Based on 299Cepheids with heliocentric distances $r<20$ kpc and pulsation periods$P\geq5^d$, we have found the directions of the three principal axes of theposition ellipsoid:  $L_1=281.0\pm0.1^\circ,$ $B_1=-1.9\pm0.1^\circ,$  $L_2= 11.0\pm0.7^\circ,$ $B_2=0.2\pm0.1^\circ$ and  $L_3=275.9\pm0.7^\circ,$ $B_3=88.1\pm0.1^\circ$. Thus, the line of nodes$l_\Omega=L_3+90^\circ=5.9^\circ$ is very close to the direction to theGalactic center; the Cepheid symmetry plane is inclined to the Galactic planeapproximately by $-2^\circ$ in the direction of the first axis ($L_1$). Thedirection of the line of nodes found from old Cepheids ($P<5^d$) differssignificantly and is $l_\Omega=298^\circ$. The elevation of the Sun above theGalactic plane has been estimated from 365 closer stars ($r<4$ kpc) without anyconstraint on the pulsation period to be $h_\odot=23\pm5$ pc.

Orientation Parameters of the Cepheid System in the Galaxy