Aim <p>To explore the fertility preservation decision-making experiences of adolescents and young adults with hematologic diseases and their families in China, and to inform culturally sensitive clinical practices.</p> Methods <p>This descriptive phenomenological study used semi-structured interviews with 26 participants from 21 families, including 14 patients and 12 family members, recruited from three tertiary hospitals in Wuhan and Taiyuan between July 2023 and December 2024. Data were analyzed using Colaizzi’s seven-step method.</p> Results <p>Three core themes emerged: (1) informed experiences of fertility preservation, including physician-family communication and patients’ and families’ impressions of the information provided; (2) factors influencing fertility preservation decision-making, including urgency of disease treatment, financial burden, understanding of reproductive toxicity and fertility preservation, uncertainty about disease prognosis, family involvement, and traditional culture; (3) post-decision planning and expectations about parenthood, with some participants who did not pursue fertility preservation expressing hope for medical advancements to address future fertility needs or considering adoption.</p> Conclusions <p>The timeliness of fertility preservation discussions for adolescents and young adults with hematological diseases needs improvement. Decision-making is influenced by both objective factors, including treatment urgency and financial considerations, and subjective factors, such as understanding of reproductive toxicity and family involvement. Early, personalized discussions, culturally sensitive decision-support tools, and the inclusion of fertility preservation in health insurance policies are essential to improve informed decision-making and enhance clinical practice.</p>