Pear (Pyrus communis) tends to have erratic productions in Uruguay, presenting self-incompatibility and floral inter-compatibility, with an estimated important role of parthenocarpy in Williams. Causes of variability in production are numerous, being the variation of rate in pollination a determining factor. The objective of this work was to characterize reproductive biology and evaluate genetic compatibility of cultivars "Abate Fetel" and "Williams" with other pollen sources, for Uruguayan agroclimatic conditions.