A liquid level detection apparatus includes a resistance plate which has a conducting pattern formed on a board, the conducting pattern including a first slide portion, a second slide portion, a plus electrode electrically connected to the first slide portion, and a minus electrode electrically connected to the second slide portion, a float which moves in accordance with a change of a liquid level, a float arm connected to the float, a sliding arm which slides over the resistance plate in accordance with a pivotal movement of the float arm, a plus connection terminal connected to the plus electrode, a minus connection terminal connected to the minus electrode, and a protective layer formed on the plus connection terminal so as to cover the plus connection terminal.