High-Q end-coupled half-wave coplanar line resonators are fabricated by using EuBa2Cu3O7-δ film sputtered on a MgO substrate. The maximum loaded Q value is 4500 and the unloaded Q value is 12500 at 28 K and 3.9 GHz. The surface resistance Rs is estimated from the Q values and the lowest Rs value is 28 µΩ at the same temperature and frequency. This value is two orders of magnitude lower than that of Cu. The minimum Rs sensitivity in the measurement with a coplanar resonator is also discussed. The estimated sensitivity is lower than 10 µΩ below 10 GHz.