[en] In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of pesticides, sufficient knowledge of entomological populations is needed. Here, a systematic monitoring of insect diversity and abundance in a conservatory orchard of Gembloux was performed. Combining yellow traps and visual observations, 19 pest and 34 beneficial families were identified among the 10766 and 3985 insects caught in yellow traps and visual observations respectively. Calculation of diversity indices allowed us to demonstrate the variability according to fruit tree species and insects observation method. Highest insects diversity was registered in apple, then in cherry and finally in the apple-pear association and plum. Pests and beneficials represented 27% and 39% of the insect collections respectively. Aphids represented from 81% to 95%of pests depending on fruit tree species and observation method. The predominant specie was Brachycaudus helychrysi (Kaltenbach). Aphidophagous guild was largely present and mainly constituted by coccinellids and hoverflies. Harmonia axyridis Pallas and Episyrphus balteatus De Geer were the most abundant. Aphididae was found to be the most common orchard pests with a range of related aphidophagous beneficials. These results highlight the need leading to potential reasoning .