tWater deficit is the most limiting factor for yield and fruit-quality parameters in papaya crop (Car-ica papaya L.), deficit-irrigation (DI) strategies offering a feasible alternative to manage limiting waterresources. When DI is applied, it is crucial to assess the physiological status of the crop in order to main-tain the plant within a threshold value of water stress so as no to affect yield or fruit-quality parameters.The aim of this work was to evaluate the feasibility of thermal imaging in young papaya plants to assessthe physiological status of this crop when it is subjected to different DI regimes, studying the relation-ships between the changes in leaf temperature (Tleaf) and in the major physiological parameters (i.e.,stomatal conductance to water vapor, gs; transpiration, E; and net photosynthesis, An). The trial was con-ducted in a greenhouse from March to April of 2012. Plants were grown in pots and subjected to fourirrigation treatments: (1) a full irrigation treatment (control), maintained at field capacity; (2) a partialroot-zone drying treatment, irrigated with 50% of the total water applied to control to only one side ofroots, alternating the sides every 7 days; (3) a regulated deficit irrigation (50% of the control, applied toboth sides of plant); (4) and a non-irrigated treatment, in which irrigation was withheld from both sidesof the split root for 14 days, followed by full irrigation until the end of the study. Significant relationshipswere found between Tleafand major physiological variables such as gs, E and An. Additionally, significantrelationships were found between the difference of leaf-to-air temperature (Tleaf–air) and gas-exchangemeasurements, which were used to establish the optimum range of Tleaf–airas a preliminary step to thecrop-water monitoring and irrigation scheduling in papaya, using thermal imaging as the main sourceof information. According to the results, we conclude that thermal imaging is a promising technique tomonitor the physiological status of papaya during drought conditions.