A focused PROTAC library was developed to degrade both IGF-1R and Src proteins, which are associated with various cancers. PROTACs with IGF-1R and Src degradation potentials were synthesized by tethering different inhibitor warhead units and the E3 ligase (CRBN) recruiting-pomalidomide with various linkers. The designed PROTACs 12a–b inhibited the proliferation and migration of MCF7 and A549 cancer cells with low micromolar potency (1–5 μM) in various cellular assays.