Two novel decanuclear Ln(III) compounds (Ln = Pr for 1, Nd for 2) have been solvothermally obtained by using p-tert-butylcalix[8]arene (H8TBC8A) and phenylphosphonate (PhPO3H2) as ligands. Single crystal X-ray diffraction studies reveal that both compounds are stacked by dumbbell-like Ln10 clusters, which are capped by two TBC8A8 − supports and linked by four complementary PhPO32 − ligands as well as other bridging anions. In addition, the self-assembly behavior of both compounds are interesting: the cationic Ln10 cluster layers are separated by the layers of H6TBC8A2 − ligands. Moreover, the luminescent and magnetic properties of both compounds were examined.