The present invention relates to a monofilament with a segmented pie structure formed by conjugated spinning of degradable polymers and non-degradable polymers, a hernia mesh having improved flexibility and biocompatibility, and a preparation method of the monofilament. More specifically, the hernia mesh of the present invention having improved flexibility and biocompatibility is prepared using the monofilament obtained by conjugated spinning of degradable polymers and non-degradable polymers into a segmented pie form, to control it to be gradually degraded in the body, whereby the stiffness of the early stage is removed, and thereby the foreign body sensation is also removed.