This study examines the adaptation of Islamic family law in responding to the childfree phenomenon among urban Muslim communities through the framework of maqāṣid al-sharī‘ah, particularly the principle of ḥifẓ al-naṣl. The increasing acceptance of the childfree lifestyle within contemporary urban society has generated significant legal, social, and religious debates, as the voluntary decision not to have children is often perceived as contradicting Islamic values and the pro-natalist culture of Indonesian Muslim society. This research employs a normative juridical method using statutory, conceptual, and maqāṣid al-sharī‘ah approaches, supported by qualitative analysis of legal materials and contemporary socio-religious discourse. The findings reveal that Islamic law does not explicitly obligate every married couple to have children; however, the preservation of lineage remains a fundamental objective of Islamic family law due to its close relationship with family continuity, social welfare, and the sustainability of Muslim civilization. The study further demonstrates that childfree decisions motivated solely by radical individualism and hedonistic orientations tend to conflict with the substantive values of ḥifẓ al-naṣl, whereas decisions grounded in reproductive health concerns, psychological readiness, economic limitations, environmental considerations, and responsible parenting may still be accommodated through contextual and maqāṣid-oriented ijtihād. The novelty of this study lies in reconstructing the interpretation of ḥifẓ al-naṣl from a purely biological-procreative orientation toward a qualitative-humanistic framework emphasizing psychosocial well-being, family welfare, and reproductive dignity within contemporary Islamic family law discourse.