Abstract Multicolor electrochromics have emerged as a promising solution for achieving active color modulation akin to chameleon‐like adaptive camouflage. However, the development of electrochromics with full‐color tunability still remains challenging, given the weak molecular polarity of inherent active materials and the difficulty in forming polarizer orbitals under varying applied voltages. Employing molecular polarity adjustments, a novel electrochromic polymer is successfully developed with a donor‐gradient design of molecular architecture, enabling comprehensive full‐color tunability. The polymer demonstrates outstanding overall electrochromic performance, including fast switching (around 1.4 s), high coloration efficiency (395.1 cm 2 C −1 @550 nm) and excellent reversibility (over 92% retention after 5000 cycles). Leveraging the full‐color tunability and rapid response, the electrochromic polymer is further integrated with sensing and control modules to create an environmental adaptive camouflage prototype system capable of seamlessly blending colors with dynamic background environments. This work is expected to provide a straightforward approach for developing full‐color electrochromics for electrochromic camouflage applications.