Could you clarify which Naruto series you're referring to, as there are several iterations of the franchise? Assuming you're talking about the original Naruto anime and manga, the question "Who is the weakest shinobi in Naruto?" is quite subjective and can depend on various factors like skill sets, experience, and even the situation at hand. However, if we're considering the main cast and their initial abilities, it's possible to argue that some characters, like Sakura Haruno or Ino Yamanaka, may have been perceived as weaker than their peers due to their lack of innate combat abilities or specialized techniques early on in the story. But it's important to note that as the series progresses, these characters grow and develop their skills, becoming formidable shinobi in their own right.