Abstract: By applying real option game theory and CGE theory, the optimal timing and the equilibrium price under the condition of imperfect information for the controlling shares transfer are given for the company with debt, and the sensibility analysis is made for the main factors which affect the optimal timing and the equilibrium price. The result shows that cassuming other conditions remains unchanged, it the greater the scale of the target company, the smaller M and A sunk cost, the higher the percentage the controlling shareholder holding, the greater the expected synergies,the higher the coupon, the higher the tax rate is, tren the transferring of the control is sooner, the equilibrium price is lower. The higher the industry growing the rate and the volatility is, the faster the transfer of the control is, the equilibrium price is lower and there is a double effect. The timing and the equilibrium price of the control right are not the monotonic function of the control factor.

Key words: transfer of controlling rights, real options, optimal timing, equilibrium price, the company with debt