Tear calcium contents were measured in 30 normal subjects divided into six groups of 5 individuals each, age ranging from the second to the seventh decade. No significant difference was found among the age groups. A mean of 4.40 mg of calcium/100 ml was determined for the 30 subjects with a standard deviation of 1.22 and a range of 2.60–7.60 mg/l00 ml. The tear calcium as percentage of the serum calcium was similar in the six groups and a mean of 45.68 was found for the 30 subjects. This figure is quite similar to that of serum ionised calcium as a percentage of the total serum calcium values obtained by different authors.