PCLIM is an international network of scientists interested in the responses of the pine processionary moth Thaumetopoea pityocampa to climate change, a winter-active insect whose northward expansion is acknowledged as a bioindicator of winter warming. PCLIMdb is a database of their observations on the phenology of the species throughout its range. The database consists in an annual monitoring of caterpillar colonies to score the most advanced larval instars occuring in mid-winter, when temperatures are the lowest and larval moulting is the most unlikely (thereby making the survey less sensitive to small variations in sampling dates). These annual snapshots are being completed since 2015 and allow benchmarking phenological differences among regions and generations over a geographic extent unique for an insect. This database is currently restricted to PCLIM members but will be made publicly available with a DOI when the corresponding data paper is published. The data is replicated at https://entrepot.recherche.data.gouv.fr/, but currently restricted in access to the contributors (until the data paper is published).