Abstract：Proportionality in the Narrower Sense can cause the abuse of discretion, inadequate measure of benefits and results-oriented analysis, so we should make proportionality in the narrower sense more specific to limit balancing. The concretization of proportionality in the narrower sense can be mainly divided into two modes. One is the mathematical model from the perspective of the balancers, the other one is the discourse mode from the perspective of the parties. The essence of the principle of proportionality in the narrow sense is the judgment of the necessity of purpose. Its functions are to protect the human rights and to make sure that the whole social welfare is promoted. In order to eliminate the irrationality of proportionality in the narrower sense as much as possible, we should construct a new concretization mode from the common perspective of the balancers and the parties. We should use cost benefit analysis and the formula of the equilibrium to calculate the proportional value of the less restrictive mean which can cause damage and promote interest, and then balance whether the less restrictive mean is comply with proportionality in the narrow sense according to the formula of the equilibrium.