  Let (M,I, \omega, \Omega) be a nearly Kaehler 6-manifold, that is, an
SU(3)-manifold with the (3,0)-form \Omega and the Hermitian form \omega which
satisfies $d\omega=3\lambda\Re\Omega, d\Im\Omega=-2\lambda\omega^2$, for a
non-zero real constant \lambda. We develop an analogue of Kaehler relations on
M, proving several useful identities for various intrinsic Laplacians on M.
When M is compact, these identities bring powerful results about cohomology of
M. We show that harmonic forms on M admit the Hodge decomposition, and prove
that H^{p,q}(M)=0 unless p=q or (p=1, q=2) or (p=2, q=1).
