The present invention relates to a method (1) for comminuting macroalgae in a process chamber (4), wherein at least one first conveying device (7.1) and at least one first comminuting device (7.2) are arranged in the process chamber (4), the method (1) comprising the steps of: filling the macroalgae (8) into the first conveying device (7.1); feeding the macroalgae (8) to the first comminuting device (7.2) by means of the first conveying device (7.1); comminuting the macroalgae (8) in the first comminuting device (7.2) by means of pressure, friction and/or shearing; and discharging the comminuted macroalgae (8) from the first comminuting device (7.2) by means of subsequently conveyed macroalgae, wherein the moisture content of the macroalgae (8) in the first conveying device (7.1) is set so that the comminuted macroalgae (8) are pasty when they are discharged from the first comminuting device (7.2). The invention also relates to a corresponding device (3).