A calorimetric study was made of the three condensed states (glass, liquid, and crystal) of 1-pentene in the temperature range 13-300 K. The glassy states were formed by two different methods, vapor deposition (VQ) and liquid quenching (LQ). Each glass was prepared in situ in each sample cell of two adiabatic calorimeters designed for general purpose and for VQ samples. The glass transition temperatures (T-g congruent to 70 K) and heat capacities of the two glasses were essentially the same. Much larger exothermic effect due to the structural relaxation was observed below T-g for the VQ glass than that for the LQ glass. The enthalpy relaxation process was analyzed in terms of the Adam-Gibbs (AG) equation. The relaxation processes for the VQ sample exhibited linear relations in log tau vs (TSc)(-1) plot (tau, enthalpy relaxation time; S-c, configurational entropy) at all of the observed time and temperature ranges. Taking the effect of relaxed entropy into account, the residual entropy of the VQ and LQ samples was estimated to be 31.69 and 19.66 J K-1 mol(-1), respectively.