Abstarct: Since microfluidic systems are of the modern issues and technologies, have attracted researchers' attention. The main purpose of the thesis has been devoted to the investigation of Lab-On-Disk microfluidic systems using Lattice Boltzmann Method which is one of the most robust methods in numerical simulation. This simulation not only provides development of LBM in a new context but also prepare the possibility of comprehensive understanding about the performance of these systems through investigation of influential parameters. Since LBM particularly Lee's method has been employed to simulate the two immiscible phase, the method, its features and its related boundary conditions have been presented in details. In this regard, according to the proposal, in the last section of the thesis, all results in various steps of validation and their purposeful development have been rendered. In section related to droplet dynamic, increase of droplet generation has been assessed through aligning a funnel or triangular obstacle. Both LOD and LOC systems have been inquired. In these sections, not only different flow regimes but also some innovations have been introduced. Hence, some techniques have been represented in order to making delay in second phase releasing known as valving and augmentation of droplet generation rate applicable in Nucleic Acid assays. Furthermore, effects of change in channel geometry, related dimensionless parameters and combination of the influential parameters have been studied.