To provide a sliding bearing having improved seizure resistance and wear resistance under high bearing pressure and low speed sliding states while maintaining characteristics stably for a long time without lowering the strength of a sintered sliding material, and to provide a working machine connecting device using the same.

A lubricant mixture formed by dispersing lubrication oil into wax in terms of liquid is filled into a pore of a Cu alloy. The lubricant mixture is formed so that the lubricating oil containing a 80-99.5 wt% extreme-pressure additive is dispersed in the solid wax of 0.5 wt% or higher and lower than 20 wt% at room temperature in terms of liquid. Its dropping point is 20C or higher and lower than 60C, and the viscosity of the lubricating oil in the lubricant mixture at 40C is lower than 220 cSt.