In this article, we give a sufficient and necessary condition for every Jordan {g,h}-derivation to be a {g,h}-derivation on triangular algebras. As an application, we prove that every Jordan {g,h}-derivation on
\tau ({\mathscr{N}})
is a {g,h}-derivation if and only if
\dim {0}_{+}\ne 1
or
\dim {H}_{-}^{\perp }\ne 1
, where
{\mathscr{N}}
is a non-trivial nest on a complex separable Hilbert space H and
\tau ({\mathscr{N}})
is the associated nest algebra.