The growing popularity of Light Emitting Diode (LEDs) for lighting in controlled environment agriculture has implications in pest management, as insect development, reproduction, and survival can be affected by lighting factors. The objective of this experiment was to investigate the effects of sole-source light quality on green peach aphid (Myzus persicae) populations reared on lettuce plants (Lactuca sativa). Lettuce seedlings were transplanted and grown under high pressure sodium (HPS, control), white LED, 50:50 red:blue LED, and 90:10 red:blue LED. Twenty adult aphids were then placed on each of six plants under lighting treatments and. Aphid numbers were counted after 2 weeks. White LED lights promoted higher aphid populations relative to those under HPS lights, 50:50, and 90:10 Red:Blue LED lights, averaging 49 aphids per plant under white light, and between 5-11 aphids per plant under the other treatments. Light quality impacted plant dry weight, with HPS lighting producing a higher dry weight yield than 50:50 Red:Blue lighting, and white lighting producing a higher dry weight yield relative to HPS, 50:50 Red:Blue, and 90:10 Red:Blue. More studies on the impacts of LED lighting on insect populations can help elucidate the role of high precision lighting in pest management.