The negative assessment on Yoon's conduct of state affairs gained 2.5 percentage points to 50.2 percent, according to local pollster Realmeter.
Support for the ruling conservative People Power Party dipped 1.3 percentage points over the week to 43.5 percent last week.
The main liberal opposition Democratic Party's approval rating rose 0.8 percentage points to 40.3 percent.
The minor progressive Justice Party garnered 4.4 percent of support score last week, up 0.2 percentage points from the prior week.
The results were based on a survey of 2,514 voters conducted from last Monday to Friday. It had plus or minus 2.0 percentage points in margin of error with a 95-percent confidence level.
Latest comments