Yvette Cooper's intervention comes after claims David Cameron blocked plans drawn up by Home Secretary Theresa May to significantly curb the use of the controversial power.
In a letter to Mrs May, Ms Cooper said:
[This issue] goes to the heart of people's trust in the police and the misuse of stop-search has the potential to undermine effective community policing.
I hope that you will not give in to the Prime Minister's opposition to change.
Everyone agrees that the police need to have powers to stop and search individuals suspected of crime or to prevent a serious threat.
Intelligence-led targeting of suspected criminals helps to cut knife crime and youth killings.
However, while targeted action helps cut crime, the reality is too many searches are not targeted at all
Ms Cooper alludes to figures that show 27% of the 8,783 stop and search records reviewed by HM Inspectorate of Constabulary between October 2012 and April 2013 did not include sufficient grounds to justify the lawful use of the power.
More top news
Three men have been arrested in Sweden on suspicion of taking part in a rape that was streamed live on Facebook.
An 11-year-old girl has died in a three-car motorway crash.
They wanted it - all power to British courts. Now they've got a taste of what it means. And they might not like it.