Abstract. The Littlewood-Paley theory is extended to weighted spaces of distributions on [−1, 1] with Jacobi weights w(t) = (1−t) α (1+t) β . Almost exponentially localized polynomial elements (needlets) {ϕ ξ }, {ψ ξ } are constructed and, in complete analogy with the classical case on R n , it is shown that weighted Triebel-Lizorkin and Besov spaces can be characterized by the size of the needlet coefficients { f, ϕ ξ } in respective sequence spaces.