The datasets contain insect numbers, plant biomass, successful attacks of parasitoids, and behavioural response of parasitoids. The data are based on direct observations of insects and plants in field and laboratory experiments testing for the impact of different spectra of artificial light at night on an experimental insect food web with coloured near-monochromatic LEDs, with a single peak emittance across the visible and near-UV spectrum at wavelengths of 385, 447, 469, 475, 518, 607 and 630 nm plus a dark control. The dark control was exposed to the natural background light levels at night. We kept photon flux similar to the output of a white light LED at 20 lux, for all light treatments apart from the UV treatment. Data collection was done in a field site, and controlled temperature room at Penryn Campus of University of Exeter, Penryn, UK. The field experiment was set up on 3rd June 2017 and ran for 17 weeks, while the additional experiments were conducted between summer 2017 and summer 2018. The data have been sampled as part of the NERC project NE/N001672/1 “Effects of artificial light on multi-trophic population dynamics”.