We have made a series of single‐level dc superconducting quantum interference devices (SQUIDs) from 4‐&mgr;m‐thick TlBaCaCuO films with large grain sizes and operated them in liquid nitrogen. Although device characteristics could not be precisely controlled, some devices had white‐noise levels that approached thermally limited noise above ∼1000 Hz. In addition, devices with 5 and 80 pH loop inductances had 1/ fnoise levels at 10 Hz of 2×10−29and 5×10−29J/Hz, respectively. The noise levels at these frequencies are comparable to commercial rf SQUIDs operating in liquid helium, but the hysteresis of the voltage‐flux characteristic of the highTcSQUIDs remains large.