The temperature dependence of heat capacity of 1,4-diisocyanatobutane in crystalline and liquid states was determined by precision adiabatic vacuum calorimetry in the temperature range (8 to 360) K at standard pressure mainly with an uncertainty of +/-0.2%. Thermodynamic characteristics of fusion, the first and the second cryoscopic constants, the isochoric heat capacity C-v. and its lattice C-v,C-lat, and atomic at C-v.al components were estimated. The data were used to calculate the standard thermodynamic functions C-p,m(o)/R, Delta(o)(T)H(m)(o)/R, Delta(o)(T)S(m)(o)/R and Phi(m)(o)/R = Delta(o)(T)S(m)(o)/R =Delta(o)(T)H(m)(o)/TR (where R is the universal gas constant) over the range T --> (0 to 360) K. The energy of combustion was measured at T = 298.15 K by the bomb calorimetry. The standard thermodynamic characteristics of formation, namely, the enthalpy Delta(f)H(m)(o), the entropy Delta(f)S(m)(o) the Gibbs function Delta(f)G(m)(o) and In K-f(o) of 1,4-diisocyanatobutane were evaluated at T = 298.15 K. (C) 2005 Elsevier Ltd. All rights reserved.