A method for producing a microfluidic device includes the following method steps: a) arranging a thermoplastic elastomeric film between a base substrate and a cover substrate, at least one of the substrates has at least one depression configured to form a microfluidic chamber with a depression opening on the side of the substrate facing the elastomeric film, b) applying pressing power to the arrangement to compress the elastomeric film between the base substrate and the cover substrate, in which process the thickness of the elastomeric film is reduced, c) forming, by laser beam welding, at least one weld joining the thermoplastic elastomeric film, the base substrate and the cover substrate, and d) removing the pressing power to prevent capillaries from forming between the base substrate and the cover substrate.