Besides the health problems and economic losses, not managing the menstrual cycle successfully also leads to environmental pollution and affects millions of individuals around the world. Among the reusable menstrual hygiene products, menstrual cups come to the forefront, thanks to their minor environmental effects. This study aims to compare the menstrual cup and single-use menstrual hygiene products regarding the level of user knowledge and awareness “being green” on the environmental effects. The study is carried out between April and May of 2021 on menstruating individuals aged 18–49 years. Among 3365 individuals reached within the scope of the prior study, 298 individuals using menstrual cup and 596 individuals using single-use products were selected. Based on the literature, a survey form consisted of 16 items is prepared by authors questioning the “being green” about the environmental effects of menstrual hygiene products (EKMP). The survey is published online on Twitter and responds are collected using Google Forms. In all the items with statistically significant differences between responded questions in terms of “green” answer percentages in EKMP, it was found that menstrual cup users have a higher percentage of green answers (p < 0.001). In further analysis, as the aged advanced, EKMP scores were higher among menstrual cup users and those expressing concerns about the negative effects of menstrual hygiene products on environmental health. Increasing knowledge and awareness on the environmental effects of menstrual hygiene products, and especially the environmental effects of single-use menstrual hygiene products, might raise the demand for reusable products.