A convenient and eco-friendly approach to fabricate high-quality copper layer on ceramic via surface modification combined with electroless plating is introduced in this paper. Through the surface modification of polydopamine, alumina ceramic substrate is capable of adsorbing silver ions, which could create an activating layer to catalyze the subsequent electroless copper plating (ECP) at low temperature. The finding that modification could obviously enhance the adhesion between substrates and copper layers are evaluated by water contact angle measurement, XPS, FT-IR, SEM, EDS and adhesion tests. Moreover, after 30 min of ECP, the resulting deposited copper layer presents an excellent performance in adhesion (highest level in ASTM D3359) and conduction (up to 4.2 × 107 S ⋅ m−1, nearly 70% of bulk copper). This technology might provide a potential way to realize surface metallization on ceramic substrates applied in electronic circuits and devices.