The toilet apparatus includes a main part and a toilet seat. The main part includes a function part, and a case cover covering the function part. The main part is attached on a toilet bowl. The toilet seat is attached rotatably to the case cover. The toilet seat has a closed state and an open state. The case cover includes an extending portion, a height of the extending portion becoming low toward forward, and a toilet seat pivot support portion provided backward the extending portion, and pivotally supporting the toilet seat. The toilet seat includes a first portion positioned forward the case cover in the closed state, and a second portion rising backward from the first portion in the closed state, overlapping the extending portion, and being pivotally supported to the toilet seat pivot support portion.