The eriococcid species, Eriococcus araucariae (Muskell) is considered as an economic pest of Araucaria excelsa at Montazah garden, in Alexandria Governorate, Egypt. This study was carried out from June, 1998 till May, 1999. The obtained data revealed that the numbers of this insect were relatively low in autumn and winter months, then increased from the beginning of May to a total number/tree 72.0 +/- 1.60; continued its increase to reach 200.3 +/- 36.9/tree from the 2nd half of May and during June, July and August, with the highest number of inspected individuals (641.3 +/- 76.8/tree) in the 1st half of July. Thereafter, population began to decrease again from the beginning of September up to the end of April, decreased numbers 51.3 +/- 2.5/tree in the 1st half of September and (1.3 +/- 0.1/tree) in the 2nd half of October. Similarly, the occurrence of both immature stages and adults was also month-dependant all the year round. Adult males appeared three times in June, January and late March. There was a positive and significant relationship between the total population of E. araucariae and the daily mean temperature, wind speed and day light. This relation was negatively significant with the relative humidity.