Tetranychus urticae Koch (Acari: Tetranychidae), is a major phytophagous mites worldwide. Three essential oils of sweet orange, Citrus sinensis (L.) Osbeck (Rutaceae), Eucalyptus, Eucalyptus globulus Labill. (Myrtaceae), and Moringa, Moringa oleifera Lam. (Morngaceae), were subjected to both laboratory and semi-field studies for toxicity against T. urticae adult female. The tested essential oils were purchased as pure oil from National Research Center (NRC), Dokii, Giza, Egypt. Results indicated that mortality increased as both time and concentration increase. Eucalyptus oil was more efficient than Moringa and Sweet orange. After 72 hours of exposure to T. urticae adult females, LC₅₀ values were 0.106, 0.139, and 0.197% for Eucalyptus, Moringa and Sweet orange, respectively. For the LC₅₀ concentrations examined, a significant decrease in the total number of eggs deposited during seven days was observed. Under semi-field conditions, the LC₅₀ values for the tested essential oils against T. urticae were assessed for effectiveness on cucumber plants. The reduction percentage of T. urticae was 73.06, 69.07, and 67.57% for Eucalyptus, Moringa and Sweet orange, respectively after seven days of application without significant differences.