No. Umami is one of the five basic tastes—the savory, meaty quality you notice in foods such as tomatoes, aged cheese, mushrooms, and soy sauce. It is triggered mainly by free glutamate and related compounds that occur naturally in many foods.
MSG (monosodium glutamate) is a manufactured seasoning: the sodium salt of glutamic acid. It delivers the same glutamate signal that activates umami receptors, so it produces umami flavor, but it is an additive, not the taste itself. Many umami-rich foods contain natural glutamate without any added MSG. (WebMD)