[en] A new crystal of 2-aminopyridine phosphate (NC₄H₄NH₂)·H₃PO₄ has been grown and its x-ray structure and physical properties were studied. At room temperature the crystals are monoclinic, space group C2/c. The flat 2-aminopyridine cations are hydrogen bonded to the anionic [PO₄ ] groups. The interesting feature of the crystal structure is the three-dimensional network of hydrogen bonds including, among others, two strong, symmetrical O · · · H, H · · · O interactions with disordered proton locations. Symmetrically related PO₄ anions linked through these protons form infinite (PO₄)_∞ chains along the crystal a-axis. The anomalies in the temperature dependence of the electric permittivity showed that the crystal undergoes ferroelectric phase transition at T_c = 103.5 K. The spontaneous polarization takes place along the crystal a-axis, being parallel to the chains of the hydrogen-bonded PO₄. The disordered protons, thermally activated at room temperature, can be frozen at their positions in the ferroelectric phase. The order-disorder continuous type of the transition has been evidenced on the basis of the temperature dependences of electric permittivity and spontaneous polarization measurements