The incidence of most types of cancer is age-dependent and progressive ageing is rapidly increasing the number of elderly people who need treatment for cancer. Elderly patients (older than 70 years) present particular characteristics that make the choice of the correct treatment more difficult; for this reason, these patients are often undertreated and largely underrepresented in cancer trials making the experimental evidence on this topic even weaker. Only relatively recently has Health-Related Quality of Life (HRQoL) begun to be considered as one of the hard end-points for clinical cancer research in the elderly. Treatment of elderly cancer patients represents a typical situation where its assessment is particularly useful because of the expected toxicity of treatment and several unresolved methodological problems (higher frequency of illiteracy, worse compliance with the questionnaires, concomitant diseases, use of instruments not validated in the aged population). The aim of this review is to underline the importance detected by the too small number of studies on elderly QoL evaluation and the need in future trials either to improve QoL assessment in this subcategory of patients undergoing treatment for cancer or not, or find specific assessment tools to do it.