Abstract: According to the experimental data of 25 precast-prestressed-compound concrete beams,the author offers the formulas of the inclined cracking shearing force and shearing strength of the beams.They are simple and easy to use.They are in better agreement with the experimental data,preeast-prestressed-compound concrete beams compared with reinforced concrete beams.The inclined cracking shearing force is increased 40%.The shearing strength in general is increased 20-25%.The author also researches into the problem of the problem of the horizontal cracking of the beam's connection and gives the control method of calculation to avoid the horizontal cracking.