Phototherapy, a type of photoresponsive regulation of biological activities, together with additional stimuli‐responsive features, offers significant potential for enhancing the precision and efficacy of cancer treatments. To achieve tumor‐specific therapeutics, numerous studies have focused on the development of smart phototherapeutic nanomaterials (PNMs) that can respond to endogenous pathological characteristics (e. g., mild acidity, the overproduction of glutathione, the overproduction of hydrogen peroxide, the overexpression of specific surface receptors, etc.) present in the tumor and/or exogenous stimuli. Such responsiveness can effectively improve the physicochemical properties, cellular uptake, tumor‐targeting performance, and pharmacokinetic profile of PNMs. Herein, we will systematically discuss recent advances in this field. Moreover, potential challenges and future directions in the development of stimuli‐responsive PNMs are also presented to support the development of this emerging cutting‐edge research area.