Abstract : The thermocapillary (or Marangoni) effect is the mechanical result of an interfacial tension gradient induced by a temperature gradient on a fluid interface. This effect manifests itself by inducing (i) the migration of an immersed finite-size object (droplet, bubble), and (ii) a deflexion of the interface. Due to its interfacial nature, the Marangoni effect is particularly relevant at small length scales, especially in the context of two-phase microfluidics. This thesis aims at applying the thermocapillary effect locally induced by laser heating, in order to create some basic optofluidic actuators (valve, switch, sampler). A quantitative study of these actuators is presented. The laser-forced destabilization of a co-flowing microfluidic jet, leading to its breakup, is also investigated. This “optical toolbox” represents a non-contacting, and microfabricationfree approach for the production and handling of droplets in digital microfluidics. Moreover, to characterize these droplet over long times, thus considering statistically significant populations, a simple optoelectronic device has been developed for measuring the size and velocity of the droplets in real time.