It is an acknowledged fact that health benefits are derived from fruit- and vegetables-enriched diets. In particular, polyphenols, compounds bearing one or more hydroxyl groups attached to an aromatic ring, are ascribed for most of such beneficial effects. Among them, resveratrol, a phytoalexin found in numerous plant species, and more notably in grapes, has widely piqued the interest of the scientific community by virtue of its anti-aging, anti-inflammatory and anti-oxidant properties. Moreover, evidence claiming resveratrol ability to hinder processes underlying all the three steps of carcinogenesis (tumor initiation, progression and metastasization) has propelled an incredibly massive number of studies aimed at enquiring its eventual clinical potential in the fight against cancer. However, despite a large body of data pointing to the advantages of dietary resveratrol intake in respect of certain disease conditions, and cancer inter alia, its real position still remains quite ambiguous. In this uncertain scenario, the present review focuses its attention on the highly entangled relationship between resveratrol and breast cancer, attempting to shape the plethora of controversial results stemming from studies carried out on several in vitro and in vivo breast cancer models. Coping with such a tricky matter, there are so many variabilities concerning both resveratrol itself (dosage, administration, bioavailabilty, among others) and the unique molecular traits of each specific breast cancer subtype that must be taken into account when facing the dilemma: “might resveratrol be protective against breast cancer or does it rather fuel it?”.