An automation system for bioprocess monitoring and control, based on the distributed control system SIMATIC PCS7 and new online sensors, is introduced. The system realizes on-line monitoring of O2 and CO2 concentrations in the exhaust gas, cell density and size during fermentation processes by new instruments. Different fermentation phases can be clearly identified using the newly developed online sensor, which is ideal for the implementation of advanced process control strategies. Instrumentation, automation, and experimental results are presented to show the effectiveness of the control system.