Urbanization, also known as urban expansion, is more widespread than in the past. Cities often contribute to light pollution, which affects the circadian rhythms of living beings and disrupts their life cycles and migration pathways, as well as macrozoobenthos drift in urban streams. Increased inputs of microplastic particles to water also may affect macrozoobenthos in urban streams. The goal of this thesis is to determine the composition of: (i) macrozoobenthos and (ii) microplastics in drift samples collected during the day and night at two stations along the urban stream Vrapčak (Zagreb, Croatia). One of the differences between the two stations (V1 and V2) was the light intensity during the night, as station V1 has no artificial light and V2 is directly illuminated by a street lamp. Drift samples were collected every two weeks during the day and night in April and May 2021, resulting in a total of 48 drift samples. Macrozoobenthos was isolated from the drift samples and determined. The remaining sediment was analyzed for microplastic particles, while physicochemical parameters were analyzed from the water samples. Results indicate that artificial light affects some macrozoobenthos taxa, but significant differences in drift density between stations and diurnal patterns were not detected. Of all the particles analyzed that looked like microplastics (47 pieces), only two were found to be polyethylene, indicating that the input of microplastics into the Vrapčak stream is not significant. Therefore, the stream is probably not under great anthropogenic influence of this type. Most physicochemical parameters showed significant differences between the times of the day and between the stations. During the night, alkalinity and orthophosphate values were elevated at both stations, while oxygen, nitrates, water temperature, dissolved organic matter, and illumination values decreased. Drift density correlated only with flow velocity, i.e., drift density decreased as flow velocity increased.