A catalytic plate reactor (CPR) consisting of closely spaced catalytically coated plates, where endothermic and exothermic reactions take place in alternate channels is studied. The influence of several design parameters on its thermal behaviour and performance is investigated by parametric sensitivity analysis (PSA) using a dimensionless model for an infinite length reactor. Reactor temperature sensitivity with respect to ratio of inlet velocities, inlet temperature, ratio of pre-exponential factors, difference in activation energies, and heat effect numbers is investigated. It is demonstrated that different catalysts can show similar thermal behaviour and performance but exhibit different sensitivity behaviour. The latter is mainly influenced by the activation energies and the inlet temperature. It was found that the most sensitive behaviour is obtained during cold spot rather than hot spot or isothermal operation. A criterion is proposed in order to appreciate the flexibility of design and operating parameters, so that the reactor temperature is kept within an acceptable operating range.