Marek Čapek, Charles University in Prague, Faculty of Mathematics and Physics, Prague, Czech Republic The mathematical modelling of the blood coagulation process presents a challenge. In the poster we present a novel approach to such a kind of modelling. We will focus on the modelling of the blood clot emerging on the place of the vessel wall injury. The clot is the result of the series of the chemical reactions. We will restrict our model to a subset of the chemical reactions because of simplicity. The blood clot is treated as a biofilm using phase field method. The emerging equations are solved via finite element method.