This paper introduces a technology that 16 LED chips are integrated on a substrate to form a new type of high-voltage LEDs chipset. Monte Carlo method and Finite Element Method simulation are used to optimize the structure for making the best in the luminous flux, luminous efficiency and heat dissipation. Firstly, By the comparison of three kinds of high-voltage LEDs, the vertical structure, inverted trapezoidal structure and trapezoidal structure, the results show that the luminous efficiency of the entire high-voltage LEDs chipset used trapezoidal structure is the highest, the empirical data is 41.522%, which is 2.12 times than the vertical structure; this paper introduces the heat transfer performance of three kinds of high-voltage LEDs, the empirical data are 88.374°C, 82.652°C and 93.725°C. We can see that the vertical structure is the best. This paper also optimizes the high-voltage LEDs chipset, under the circumstances of the constant chip area, we change the area of the single chips, prompting the spacing between the single chips change. We get the best single chip area and single chip change, under this circumstance, we can get the best luminous efficiency and luminous flux.