Optofluidics aims in manipulating light and fluid at microscale and exploiting their interaction to create highly versatile devices that have significant scientific interests in many areas.The novelties of the integrated optofluidics are two-fold.First,fluids can be used to carry substances for analysis in highly sensitive optical micro-devices.Second,fluids can also be exploited to control light,making them tunable,reconfigurable and adaptive.In this paper,the state-of-the-art of optofluidic research is reviewed with breakthrough innovations in optofluidic devices.Several systems have been demonstrated with the integration of these optofluidic component toolkits such as a three dimensional dye laser by using the optofluidic waveguide,a Michelson interferometer by using the optofluidic gratings etc.One of the significant ideas is the realization of transformation optics device by using the optofluidic waveguide.Transformation optics represents a new paradigm for designing light-manipulating devices,such as cloaks and field concentrators,through the engineering of electromagnetic space using materials with spatially variable parameters.We demonstrate that a laminar liquid flow in an optofluidic channel exhibits spatially variable dielectric properties that support novel wave-focusing and interference phenomena as shown in Fig.1.This work provides new insight into the unique optical properties of optofluidic waveguides and their potential applications including evanescent wave sensing based on the optofluidic waveguide as a near-field photonic device such as single cell refractometer,cells bulk modulus measurement etc.In conclusion,optofluidic devices provide not only flexibility,real-time tunability and reconfigurability,but also new approach in liquid-light interaction.We anticipate that the future trends of optofluidic research are shifting from classical optics to modern photonics.