The diversity of fruit flies (Diptera: Tephritidae) in commercial guava orchards in the Northwest region of Espírito Santo, Brazil was recorded. Also, their population dynamics, correlation with climatic factors and their parasitoids were recorded. This study was carried out in three commercial guava orchards of the cultivar Paluma, located in the municipality of São Roque do Canaã, Central region of the Northwestern Capixaba territory, from October 2013 to September 2014. The population monitoring of fruit flies was done by installing McPhail traps provided with an attractive solution (BioAnastrepha®), hung ¾ of the guava canopy height, starting from the ground level. After obtaining the data, the following indexes were calculated: pupal viability (PV), parasitism (P) and fruits infestation (I). A correlation analysis was performed between the number of flies collected, and the meteorological variables of the region. A total of 31.51 kg of guava was collected, in which 18.31 kg were collected in the guava trees and 13.2 kg were found on the ground. 1,699 pupae were obtained, and from these, 442 flies emerged with three genera, Anastrepha species and one genus, Ceratitis (Ceratitis capitata Wiedemann). Only two parasitoids were obtained from the fruits from the ground, which both belong to Doryctobracon areolatus (Szépligeti) (Hymenoptera: Braconidae). The correlation analysis showed a strong correlation between the flies and fluctuating temperatures. Population peak of fruit flies occurred in February 2014.