We have studied the effect of the cooling time of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films on the properties of bicrystal Josephson junctions. In the three regions of the cooling time as 5/spl sim/6, 10/spl sim/20, and more than 30(min.), the junctions' Tc were above 87K, 50/spl sim/86K and above 86K, and the average value of the IcRn products at 77K were 0.12mV, 50/spl mu/V, and 80/spl ... [Show full abstract] mu/V, respectively. The junction's Tc, the I-V curves, and the junction parameters were changed due to the change of the cooling time. As a result, it was found that the cooling time was very important factor to determine the junction properties.