  In this paper we introduce a class of $3-$color algebras which are called
split $3-$Lie-Rinehart color algebras as the natural generalization of the one
of split LieRinehart algebras. We characterize their inner structures by
developing techniques of connections of root systems and weight systems
associated to a splitting Cartan subalgebra. We show that such a tight split
$3-$Lie-Rinehart color algebras $(\LL, A)$ decompose as the orthogonal direct
sums $\LL =\oplus_{i\in I}\LL_i$ and $A =\oplus_{j\in J}A_j,$ where any $\LL_i$
is a non-zero graded ideal of $\LL$ satisfying $[\LL{i_1}, \LL{i_2},
\LL{i_3}]=0$ if $i_1, i_2, i_3\in I$ be different from each other and any $A_j$
is a non-zero graded ideal of A satisfying $A_{j_1}A_{j_2}=0$ if $J_1\neq j_2.$
Both decompositions satisfy that for any $i\in I$ there exists a unique $j\in
J$ such that $A_j\LL_i = 0$. Furthermore, any $(\LL_i , A_j )$ is a split
$3-$LieRinehart color algebra. Also, under certain conditions, it is shown that
the above decompositions of $\LL$ and $A$ are by means of the family of their,
respective, simple ideals.
