In this thesis we investigate the simulation of turbulent flow with lattice Boltzmann scheme. This thesis contains eight chapters. The first chapter is introduction of thesis. The second chapter discusses about method with kinetic-based approach for fluid flow computations. In chapter 3 the lattice Boltzmann method is introduced as completed form of LGA. In this section the procedure has been explained. We show how to Discrete the phase space, and with this iscreted space we Discrete the Boltzmann equation. the algorithm of computer code has been showed at the end of the chapter. the boundary condition has been discussed in chapter 4. We separate the B.C in two part: 1-open boundary condition. 2-solid boundary condition. The open boundary conditions ontains 4 part: 1-peryodic B.C. 2-symetric B.C. 3-B.C with known velocity at boundary. 4-zero gradient at out-let. For solid boundary condition the Bounce Back on Links (BBL) has been choosen. In chapter 5,turbulent modeling has entered in LBE scheme. We used Large Eddy Simulation(LES) for solving the turbulent flow. This choice is for good result has captured in LBE-LES in pervious works. After filtering the BGK equation, a eddy viscosity has been produced. This eddy viscosity changes the relaxation time, and the collision relaxation time has changed. For compute the eddy viscosity,smagorinsky model has been used. In high Raynolds number the LB method has some noises in pressure and velocity fields. In chapter 7 We introduce multiple Relaxation time(MRT) to reduce these oscillations. We discussed about two dimensional MRT, and the collision frequency for each nodes has been suggested. The LES simulation always needs a fine mesh, and the simulation have to be in three dimensions, so the number of grid points are too much and get a lot of memory and time. We suggested using multi block method that Yu et a suggested to decrease grid points. We have modified Yu algorithm by substituting molecule relaxation time with total relaxation time(a eddy viscosity relaxation time added to molecule relaxation time).chapter 8 contains the results. First Turbulent flow around a wall-mounted cube and turbulent square jet flow has solved. We used single relaxation time SRT) for these two cases. The results are near to experiments but some oscillations can be observed. Then we simulate a flow in open channel junctions with and SRT and MRT. The SRT results are more noisy than MRT results, and the difference are obvious. At the end of thesis multi-block LBE has used to simulate flow in open channel junctions, because of high Reynolds number we has seen using MRT in this method are necessary. Key words: lattice Boltzmann, turbulent flow, multi block method, LES, MRT