This study investigates the state of alternative-academic careers (alt-ac) in Library and Information Science (LIS) within China, based on the transformation of the LIS academic market over a 5-year span (2018–2022). The study employs a unique dataset of job postings collected through first-hand field investigations and meticulous manual preprocessing. A comprehensive analysis of the dataset was conducted using a combination of the BERT-BiLSTM-CRF model for named entity recognition, social network analysis for examining interdisciplinary interactions, and descriptive statistics for characterizing the distribution and trends of alt-ac positions. The results reveal that alt-ac positions account for 48.3% of the total demand in the field, distributed across nine categories: academic research institutions, government departments, military organizations, public libraries, and others. Each category exhibits unique developmental patterns. Over 20 distinct alt-ac roles were identified, such as data librarians, competitive intelligence specialists, transformative OA agreement negotiators, and scholarly communication experts, highlighting the ongoing emergence of new positions in response to institutional evolution. Descriptive statistics showed that the demand for alt-ac positions was notably concentrated in economically advanced regions, with the East China region accounting for 32.58% of the total positions, surpassing the proportions in North China (26.22%) and South China (13.86%). Social network analysis revealed substantial interdisciplinary interactions between LIS and other areas, such as computer science and public administration, suggesting potential opportunities for collaboration and competition. The findings emphasize the growing significance of alt-ac in China’s LIS field and provide insights into the dynamic landscape of the academic job market, offering implications for LIS education and workforce development strategies.