The invention relates to a microfluidic micromechanical system having integrated active elements (7) and a method for microfluidic process control in a microfluidic micromechanical system. According to the invention, the microfluidic system comprises integrated active elements (7), which can be activated without auxiliary energy by means of ambient variables that can be influenced and which are designed to bring about active functions as a result of the change of the swelling state thereof or the mechanical properties thereof. The microfluidic micromechanical system further comprises at least one structural support (2) having at least one first (3) and one second (4) channel, wherein a reaction chamber (6) bounded by active elements (7) is formed in an overlapping region (5) of the first and second channels.