Due to climate change and rapid growth in global population, it is necessary to find new food sources that satisfy nutritional needs and can be cultivated in a fast and simple way, with minimal environmental effects. Microgreens, young plants containing the stem, cotyledons and the emerging first true leaves, have proven to be a promising new „functional food“ that meets those conditions. The Brassica genus stands out as one of the most commonly grown for human consumption and thus one of the most readily available for the production of microgreens. Vegetables of this genus are known for their high concentrations of nutrients and phytochemicals useful for the human organism, and microgreens turn out to be an even richer source of some of them, such as different vitamins, pigments, polyphenols and glucosinolates. Many of these bioactive compounds have extremely positive effects on human health, thanks to their antioxidant, anti-inflammatory, antidiabetic and anticancer properties, which is why consumption of microgreens rich in them is proposed as an effective mean of preventing and treating various chronic diseases. This paper presents an overview of information about the phytochemical and nutritional composition of Brassica microgreens, especially bioactive compounds and their effects in the human organism, in order to show the potential of microgreens as the new „superfood“.