In conclusion, the measurement of both vitamin D and serum albumin on COVID-19 patients’ admission, and their combined evaluation, could provide a relatively simple prognostic evaluation that clinicians could take into account (alongside with other multiparametric prognostic scores) both for taking pragmatic decisions and to think over the underlying complex pathophysiological mechanisms that relate vitamin D and albumin depletion with a worse outcome. Here, ALB is linked to COVID-19.