To allow protected and private properties to be accessed, you should useReflectionProperty::setAccessible(bool $accessible):<?php/** Class Foo with protected and private members */class Foo { protected $bar = 'barrr!'; private $baz = 'bazzz!';}$reflFoo = new ReflectionClass('Foo');$reflBar = $reflFoo->getProperty('bar');$reflBaz = $reflFoo->getProperty('baz');// Set private and protected members accessible for getValue/setValue$reflBar->setAccessible(true);$reflBaz->setAccessible(true);$foo = new Foo();echo $reflBar->getValue($foo); // will output "barrr!"echo $reflBaz->getValue($foo); // will output "bazzz!"// You can also setValue$reflBar->setValue($foo, "new value");echo $reflBar->getValue($foo); // will output "new value"?>