Tl 2 Ba 2 Ca 2 Cu 3 O x (TBCCO) thin films with T c ≥ 110 K were grown on the yttrium-stabilized (100) zirconia (YSZ) substrates by d.c. magnetron sputtering technique. The d.c.-SQUIDS made from the TBCCO films have operated at temperatures near 100 K. The relationship between I c and T of the grain boundary junctions is I (1 - T/T c ) n , with n 1.6. This indicates that they are the long bridge junctions. The SQUIDs were biased by d.c. currents. Meanwhile, a 25 kHz a.c. flux with a peak-to-peak amplitude of φ 0 was applied through a modulation coil. The voltage across the SQUID was amplified by a factor of about 10,000 with a cooled transformer and a preamplifier. Our investigation showed that the d.c.-SQUIDs can operate near 100 K; some of them can even operate at 105 K.