One of the crucial types of sources used in the research on old age and the social and physical condition of old people are diaries. This article explores sixteenth-century diaries and chronicles of burghers from Wroclaw (Breslau), Swidnica (Schweidnitz) and Nysa (Neisse). The analysis concerned two issues: the authors' reflections on their own aging and the descriptions of their relationships with old people from the close circle. As to the latter topic, the most interesting data were found in the diary by Daniel Scheps, a doctor from Swidnica, written in the years 1574-1608. Scheps diaries contain several dozen mentions about elderly people, noted down, as can be inferred, in order to record unusual events. Those mentions indicate what age was considered the borderline between maturity and senility at that time, and to what extent people were aware of their own age in various social groups. The diary also provided some data on illnesses and the causes of old people's deaths. The diaries analyzed confirm historians' and demographers' findings as to the differences in old people's living conditions dependent on their sex. They also partly confirm previous findings on the significant share of old people in authorities.