Microfluidic devices have attracted much attention owing to its applicability in various field such as analysis and chemical reactions. However, due to the low dimension of microfluidic channels, the flow rate is extremely slow in most microfluidic systems. The low flow rate results in a well-defined laminar flow which facilitate the control of the fluids, but it can also result in the inhibition of mixing. To achieve fast mixing, complex channel structures have been introduced that complicate the fabrication process. Extremely fast mixing, on the other hand, can be achieved by operating the device in turbulent regime. In this thesis, microfluidic devices were employed for the turbulent mixing of fluids and the behavior of mixing was characterized.