Neotropical Entomology 35(2): 269-272 (2006) Use of Neem Extract in the Control of Acariasis by Myobia musculi Schranck (Acari: Miobidae) andMyocoptes musculinus Koch (Acari: Listrophoridae) in mice (Mus musculus var. albina L.)ABSTRACT -The objective of this work was to evaluate the acaricide action of neem extract formulated as a pomatum in the treatment of acariasis in mice (Mus musculus var. albina L.) naturally infected by Myobia musculi Schranck and Myocoptes musculinus Koch. Twenty parasitized animals were chosen and distributed in four groups: control (vaseline), 5%, 10% and 20% of neem. The animals were treated at 48h intervals and maintained in cages with food and water ad libitum and accompanied daily for 24 days. There was a decrease in the mean number of mites recovered after 96h with 5% of neem when compared to de others concentrations (P < 0.05). From 120h on, the concentrations of 10% and 20% were also efficient and differed statistically from the control group (P < 0.05 and P < 0.01; respectively). From 168h on, the animals treated with neem concentrations of 10% and 20% showed significant results (P < 0.01). The animals exhibit signs of hair recuperation and the mites were not observed anymore. After 216h, the hair was completely recovered and the animals remained free of the infestation in the concentrations of 10% and 20%. The neem pomatum showed acaricide action in the concentrations of 10% and 20% for mice and when used as a topical remedy, had good phlogistic and cicatrizing activity and showed no side effects.