Lehrer, 76, has anchored or co-anchored PBS' daily public television news broadcast for 36 years.
"I have been laboring in the glories of daily journalism for 52 years ... 36 of them here at the 'NewsHour' and its earlier incarnations ... and there comes a time to step aside from the daily process, and that time has arrived," Lehrer said in a statement Thursday.
PBS said on its Web site Lehrer will continue to occasionally moderate the weekly analysis on the network's "Shields and Brooks" program and will also remain involved in the editorial direction of "PBS NewsHour" and the program's producer, MacNeil/Lehrer Productions.
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