Malignant tumor is one of the disease with the highest mortality rate worldwide. In clinic, the common treatment methods include chemotherapy, radiotherapy and surgery, and majority of patient after surgical treatment also need adjuvant chemotherapy. In order to achieve targeted delivery and quickly release of the drug at the tumor site, stimuli-responsive smart nanocarrier system has received extensive attention. The smart nanocarrier system mainly include tumor?microenvironment stimuli-responsive?smart?nanocarrier system and external physical stimuli-responsive?smart?nanocarrier system. Smart nanocarrier system can transport antitumor drug in circulation stably. After arriving the tumor site, the drug can quickly release from the smart nanocarrier system after triggered by the tumor microenvironment or external physical stimuli, which could improve the drug concentration of the lesion,significantly?increase?the?antitumor?efficiency?and?reduce?the?side?effects?of?drugs.This?review?mainly?gives?a?comprehensive?overview?in?the?latest?research?and?new?development?of smart nanocarrier system, targeted smart nanocarrier system and multifunctional smart nanocarrier system. Moreover, the existingproblems are pointed out along with their possible future applications in this review.