Abstract: The range of application of the equation of state proposed by Martin and Hou for gases was extendedinto liquid region.The improvement was achieved by retaining the constant,B_,in the original equation,namelyP=(RT)/(V-b)+(A_2+B_2T+C_2e~(-5.475))T_r+(A_3+B_3T+C_3e~(-5·475))T_r+(A_4+B_4T)/(V-b)~4+(B_5T/(V-B)~5)and imposing the condition,PdV=P_0(V_v-V_l),on the equation.The constant,B_4,was then evaluatedfor a given compound.The calculated values of the saturated liquid molar volumes for carbon dioxide,normal butane,argon,methane and nitrogen,were compared with the data reported,in the reduced temperature rangefrom about 0.65 to 1.0.The average deviation was less than 5% in each case,without loss of accuracyin gaseous region.Furthermore,no additional data were required for evaluation of the constants of theimproved equation.