Many conventional therapies are used to treat various cancers. However, because of multiple problems that include low efficacy and safety issues, different strategies to treat cancer are necessary. One strategy is combination therapy. Combining drugs or other adjuvants has a synergistic effect in cancer treatments. Combination therapy permits multiple targeting through the same or different signaling pathways to overcome the limitations. Moreover, the use of nanotechnology in combination therapy permits even greater increases in efficacy. The U.S. Food and Drug Administration (FDA) has approved biodegradable polymers such as poly (D,L-lactide-co-glycolide) (PLGA) and poly (ethylene glycol) (PEG) that can be surface modified with targeting moiety for active targeting strategy. PLGA-b-PEG is used for formation of biodegradable polymeric nanoparticles for delivery of payloads. In this thesis, I report on several strategies of combination therapy using polymeric nanoparticles.