In the present study, the effects of nocturnal light level (i.e. lunar phase and artificial lighting) on the activity of wall geckos was evaluated (Tarentola mauritanica) of different ages in an anthropic environment. Data on individual behaviour were collected by direct observation and later examined by means of generalized linear mixed model (GLMM) analysis. The presence of moonlight increased the number of active wall geckos. Artificial lighting reduced the effect of moonlight on the number of active geckos but not on their individual activity. A greater number of adult geckos was found around artificial light as large individuals monopolized the best foraging sites. The ability to use artificially–lit human habitats, particularly on new moon nights, can benefit the foraging activity of nocturnal lizard species such as the wall gecko. informacion[at]ebd.csic.es Martín et al (2018) Effects of natural and artificial light on the nocturnal behaviour of the wall gecko. Anim Biodiv Conserv 41.2: 209-215