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The impact of chlorpyrifos ethyl (applied at a rate of 225 g a.i./ha) and fenitrothion (at 450 g a.i./ha), two insecticides commonly used to control desert locusts (Schistocerca gregaria Forskal), on the activity of Psammotermes hybostoma Desneux, a Subterranean, wood-eating termite, were assessed in the Tafidet Valley in the Air area, during July-December 2005. Termite activity was significantly reduced with chlorpyrifos and fenitrothion compared with unsprayed control plots. Termite activity was most affected 1-30 days (interval I) after treatment and thereafter for a period up to 60 days (Interval II). Chlorpyrifos ethyl was the more toxic insecticide, leading to 75 % and 73 % reduction in termite activity during Intervals I and II, respectively. Recovery of the termite population occurred 60 days after treatment, as reflected by resumption of feeding activity Both insecticides showed no effect on termite activity from 75-90 days after treatment.