A continuous reaction micro-reactor of modular structure comprises, arranged along a back-to-front stacking axis thereof, a first frame means, a reaction unit, and a second frame means, wherein said reaction unit comprises a process fluid channel system for continuous reaction of a plurality of feeds or reactants flowing into said reaction unit to form at least one product flowing out of said reaction unit, and a heat exchange fluid channel system for adjusting the temperature environment of said process fluid channel system, said first and second frame means are each formed as a flange, and said first and second frame means are alpressed towards each other by a plurality of tensioning means arranged along and within an outer circumference of said first and second frame means and enclosing said reaction unit.