The reaction between LH2, [pyda.H2][pydc], ( pyda = 2,6 –pyridinediamine and pydc. H2 = 2,6 – pyridinedicarboxylic acid), ligand with palladium(II) chloride leads to the formation of [pyda.H]2[PdCl4]. The crystal structure of the compound was determined by X–ray diffraction. The crystal system is triclinic with space group Pī and one molecule per unit cell. The unit cell dimensions are a = 6.900(3) Å, b = 7.898(3) Å, c = 8.025 (3) Å, with α = 103.302(14)º, β = 104.068(14)º and γ = 92.415(12)º. The final R value is 0.0602 for 1988 reflections. The presumably of the formation [pyda.H][Pd(pydc)(pydc.H)], [Pd(pydc.H)2] and [pyda.H]Cl species, was studied by IR, ESI/MS, 1H NMR, 13C NMR spectroscopy, and elemental analysis.