Social support and will to live are correlated phenomena, especially among older adults with more limited social networks. In the current study we examined longitudinal bidirectional associations between social support and will to live among those 75+ years of age. We recruited and followed a sample of Israeli adults (N = 824; M = 80.84; range 75-96 years). Structured interviews were conducted in the homes of participants who reported social support and will to live at each point of measurement. We examined a cross-lagged, longitudinal structural equation model (SEM) in which social support and will to live predict each other over time, covarying for previously reported social support and will to live. We found that both will to live and social support are largely consistent in late life. Will to live and social support reported at baseline predict levels reported 1- and 2-years thereafter. At each point of measurement, social support contemporaneously predicts will to live. Cross-over effects also emerged over time. Loss of social support at baseline (not measured in future) predicts lower will to live 1-year later. And will to live at Time 2 predicts greater social support 1-year thereafter.. These findings suggest that associations between will to live and social support are bidirectional in late life. Further research is needed to replicate findings in other cultures and over longer periods, ideally until end of life.