Disclosed is a reciprocating compressor having an assembly structure of a suction muffler, in which a supporting unit is formed on an inner circumferential surface of a resonant container of the suction muffler and a baffle is assembled in the resonant container by the supporting unit. By forming protrusions in the resonant container and inserting a baffle between the protrusions, the suction muffler can be easily and simply assembled. Accordingly, production costs can not only be reduced but also an increased noise reduction effect is obtained by precisely regulating an assembly position.