Skeletal muscle satellite cells are stem cells characterized by their multipotency and capacity for in vitro proliferation. However, primary skeletal muscle satellite cells demonstrate limited proliferative capacity in vitro, which impedes their investigation in poultry skeletal muscle research. Cell immortalization techniques have emerged as valuable tools to address this limitation and facilitate the study of skeletal muscle satellite cell functions. This study achieved the immortalization of chicken skeletal muscle satellite cells through the transduction of primary cells with TERT (telomerase reverse transcriptase) amplified from chicken (chTERT) using a lentiviral vector via telomerase activity reconstitution. While the cells successfully overcame replicative senescence, complete immortalization was not achieved. Initial functional characterization revealed that the proliferative properties and cell cycle characteristics of the immortalized chicken skeletal muscle satellite cell lines (ICMS) closely resembled those of chicken primary muscle satellite cells (CPMSCs). Serum dependency analysis and soft agar assays confirmed that ICMS did not undergo malignant transformation. Furthermore, induced differentiation experiments demonstrated preserved differentiation capacity in ICMS. The established cell lines provide a fundamental framework for developing immortalized poultry cell lines and offer a cellular model for investigating poultry skeletal muscle-related functional genes.