We are the first to study the interplay between corporate diversification and debt maturity, both theoretically and empirically. Our models predict that diversification mitigates the debt-overhang problem, making long-term debt more attractive in the presence of rollover costs. Using data on 30,135 firms from 1978 to 2022, we find that multi-division firms have debt maturities at least 1 year longer than stand-alone firms, especially when facing debt overhang. Consistent with our predictions, th