<?php

$storeid = 1;
$catid = 16;

deleteAllCategoryProducts($storeid,$catid);

function deleteAllCategoryProducts($storeid,$catid)
{
  require_once 'app/Mage.php';
  Mage::app( "default" )->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID);

  $_category = Mage::getModel('catalog/category')->setStoreId( $storeid );
  $_category = $_category->load($catid);

  $subcats = $_category->getAllChildren(true); // true to get as array
  
  foreach ($subcats as $subcatid) {
    echo 'Deleting from Category ID: ' . $subcatid . "\n";
    echo 'Deleting Product IDs: ';
    $pids = Mage::getResourceModel('catalog/product_collection')->setStoreId($storeid)->addCategoryFilter(Mage::getModel('catalog/category')->load($subcatid))->getAllIds();

    if(is_array($pids))
    {
      foreach ( $pids as $pid ) {
        echo $pid . ' ';
        $product = Mage::getSingleton('catalog/product')->load($pid)->delete();
        unset ($pids[$pid]);
      }
    }
    echo "\n";

  }
} 
?>

Change the category id and store id at the top of the script before running it. You can also remove the echo statements if you don’t want any output.

Delete All Category Products

magento

PHP