The thrombin generation test is one of the diagnostic tests currently in use as a universal method for measuring hemostatic disorders. We envisioned that conventional monitoring of thrombin generation could be miniaturized resulting in a time-saving, accurate, easy-to-operate, and cost-efficient test. For the translation of the conventional thrombin generation test to microfluidic devices, our focus was directed to parameters such as the detection limit, temperature, protein-surface interactions (i.e., hydrophilicity of microchannels), and mixing behavior. Scaling down to microchannels (e.g., capillaries) resulted in volume reduction and allowed us to study the effect of a microchannel surface (either hydrophilic or hydrophobic) on the thrombin activity. Finally, the use of a micromixer enabled us to perform efficient on-chip mixing, resulting in the successful measurement of a thrombin generation in a microfluidic device.