A novel non‐volatile organic memory device is developed based on an organic field effect transistor (OFET) with a dielectric layer of a four‐armed, star‐shaped polymer featuring a copper phthalocyanine (CuPc) core. The CuPc core unit of the star‐shaped polystyrene (CuPc‐PS4) self‐assembles to form aggregates via π–π interactions, which are isolated and dispersed in the polymer thin film. The OFET memory device employing CuPc‐PS4 shows significant hole‐trapping characteristics with a high memory ON/OFF current ratio of 107, long retention ability of over 104 s, and good endurance of more than 100 cycles, which is attributed to a flash‐type memory. The novel polymer design with CuPc core assemblies inside the polymer matrix is a promising candidate for nano floating gates in non‐volatile OFET memory.