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The results in this study are summarized as follows : First, in case that the process follows normal distribution, the proposed VSI X - CRL synthetic control chart in detecting process mean shift was performed the most excellently in aspect of statistical performance, regardless of control limit L of CRL/S control chart. Second, Detecting process shift is faster, L value is greater in small shift of process, in case that applies individual control chart, L value may be proposed more than 5 in large shift. Also, L vlaue is proper at 4～6 that detects rapidly the small shift as well as large, in case of VSI X - CRL synthetic control chart in sample size 4 or 5 that uses the most in traditional control chart. Third, in case of process mean shift δ = 1.0σ, when economic optimal parameter of VSI X - CRL synthetic control chart is at L = 5, n = 4, the expense amount is the least. The control parameters of CRL/S control chart are determined as k = 2.239, k = 0.974, d1 = 0.100 and d2 = 1.397. Proposed control chart brings cost-cutting effect of 3.04% control expense less than FSI control chart. Fourth, control cost shows a tendency to increase gradually as increasing λ, parameter of exponential distribution. There is no effect in control limit effect of each control chart by increasing λ, but sampling interval, d1 and d2, goes shortly to reduce time to find special causes. Proposed VSI X - CRL synthetic control chart in this research can use more easily than traditional control chart along with applying run rule and the performance is superior to traditional control chart. It may not be difficult to establish the optimal economic control parameters to apply the practical cost parameters in field.