  We present a detailed study of the two-parton light-cone distribution
amplitudes for $1\,^3P_2$ nonet tensor mesons. The asymptotic two-parton
distribution amplitudes of twist-2 and twist-3 are given. The decay constants
$f_T$ and $f_T^\bot$ defined by the matrices of non-local operators on the
lightcone are estimated using the QCD sum rule techniques. We also study the
decay constants for $f_2(1270)$ and $f_2^\prime(1525)$ based on the hypothesis
of tensor meson dominance together with the data of $\Gamma(f_2\to \pi\pi)$ and
$\Gamma(f'_2\to K\bar K)$ and find that the results are in accordance with the
sum rule predictions.
