This study was conducted from May to October 2008 in two villages in Chanthaburi Province: village No. 2 Tup Sai Canton (control) and village No.12 Pong Nam Ron (treatment area). Indoor residual spraying, using 10% bifenthrin WP (Bitecthrin WP) was conducted at a concentration of 25 mg/m2 with 87.3% spray coverage of the houses in the treated area. Monthly entomological studies showed that in the control area, Anopheles minimus density was significantly higher than the treatment area. A WHO cone bioassay test showed the residual effect against laboratory-bred, An. dirus persisted for up to 6 months. Community acceptability was good and most preferred insecticide spraying. 10% bifenthrin WP applied six-monthly can be used as an indoor residual spray for malaria control.