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Purpose: To characterize the rate of change of ocular surface temperature (OST) under lid manipulation after cooling the intact cornea with balanced salt solution (BSS). Methods: In a patient for refractive surgery, prior to the ablation, the temperature of the cornea was continuously recorded with a high speed infrared (350 Hz) camera. Two millilitre of chilled BSS with a temperature of 8.6 °Celsius (°C) was instilled for about 3 s. Using exponential functions, the three contributions have been determined, subjacent corneal layers, environment, and chilled BSS. Results: The mean temperature of the cornea preoperatively was 34.5 °C. After applying the chilled BSS the temperature decreased about 14 °C down to an OST of 20 °C and the time needed afterwards to get the normal (OST) temperature of about 30 °C was 40 s. Due to the inserted speculum and missing blink, OST did not reach the original OST of 34.5 °C and faded at about 32.5 °C. According to our best fitted model, absolute value of each contributing component was 31.4 °C (subjacent corneal layers), 26.8 °C (environment) and 8.6 °C (BSS). Conclusions: Applying chilled BSS to the cornea quickly reduces the temperature of the cornea with a thermal relaxation time of 3 s and a amplitude decrease of 8.6 °C. This together with a relaxation time of 7s for subjacent corneal layers, and 184 s for environment after instillation of BSS combined with a well-controlled environment provides a period of 40 s of corneal temperature below baseline, which may be of clinical benefit when applying chilled BSS immediately before or immediately after ablation.