Polystyrene (PS) is currently mainly used as a sacrificial template during pattern release upon microcontact printing or for self-assembled flat free-standing films. We hereby present a method for creating 3D microstructured free-standing self-assembled polyelectrolyte multilayer (PEM) thin films. The approach presented utilizes a sacrificial microstructured PS template which can be coated with PEM thin films, whereby dissolution of the PS facilitates a free-standing 3D microstructured PEM film. The PS templating approach allows for omitting hot embossing on silicon masters, since PS templates can be prepared by drop casting on silicon masters. The prepared PEM film offers, if gold nanoparticles are incorporated, stimuli-responsive properties like light-induced chamber opening.