By introducing the variable sampling interval feature into the bivariate double sampling generalized variance control chart, a bivariate double sampling generalized variance control chart and its monitoring method are developed. The Markov chain approach is used to calculate the adjusted average time to signal and average time to signal performances of the control chart. Then the design of the new control chart is defined and formulated as an optimization problem, which is solved by using a genetic algorithm. In comparison with the bivariate synthetic generalized variance control chart with variable sampling interval, original bivariate double sampling generalized variance control chart and bivariate double sampling generalized variance control chart based on Cornish-Fisher correction, the proposed control chart offers a better adjusted average time to signal performance. Furthermore, the advantage of the proposed control chart is illustrated with by an example.