Abstract <p>Changes in the content and composition of reserve substances—monosaccharides, polysaccharides, starch, and secondary metabolites are studied: phenolic carboxylic acids (chlorogenic, caffeic, ferulic) and abscisic acid, photosynthetic pigments (chlorophylls <i>a</i>, <i>b</i>, and carotenoids), and amounts of flavonoids in the wintering buds of the invasive <i>Acer negundo</i>, introduced by <i>Acer saccharinum</i>, <i>Acer tataricum</i> subsp. <i>ginnala</i>, and the native <i>Acer platanoides</i>, from December to April in the conditions of central Russia (Moscow). Accumulation of reserve substances was found in an average of 40% of the air-dry mass of the buds, mainly monosaccharides; however, invasive <i>A. negundo</i> had two times fewer sugars, and their composition was dominated by polysaccharides and starch. In the composition of secondary metabolites of <i>A. saccharinum</i>, caffeic acid was identified during the entire observation period, unlike other maple species, and in the frostiest period, an increase in the carbohydrate pool to almost 80% of the dry weight of the buds was noted. The dynamics of the content of forms of reserve substances and phenolic compounds and their relationship to the formation of a survival strategy for North American species of the genus <i>Acer</i> is discussed.</p>