We have measured 1/fresistance noise at room temperature in laser‐ablated YBa2Cu3Oy(YBCO) thin films over a wide range of normal‐state resistivities. Surprisingly, the high resistivity films exhibit lower normalized noise powers than the low resistivity films. The lowest normalized noise power is 100 times lower than any previously reported values for single crystals of YBCO and is comparable to the lowest noise levels found in other cuprates. Upon oxygen reduction, the noise power in the high resistivity films increases monotonically whereas it decreases in the low resistivity films. We conclude that the high noise level in YBCO is most likely intrinsic to the structure and due to conduction along the Cu‐O chains. Therefore, the low noise power in high resistivity films appears to indicate a degraded chain conductivity. ©1995 American Institute of Physics.