Why JavaScript null check doesn't working?

function readProperty(property)
{
  console.log(localStorage[property]) //Alerts “null”
  if(localStorage[property] == null)
  {
      console.log('Null chek')
      return false;
  }

  return localStorage[property];
}

log outputs "null", but ‘if()’ doesn’t work. I try with ===, its not work too. Help please.

UPD: Thanks everyone this change helped me if(localStorage[property] == 'null')

>Solution :

The keys and the values stored with localStorage are always in the
UTF-16 string format, which uses two bytes per character. As with
objects, integer keys are automatically converted to strings.

https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage

Try:

localStorage[property] === 'null'