The present invention relates to a washer fluid reservoir. The washer fluid reservoir comprises: a reservoir body which receives washer fluid; a sealing member which seals a hole formed in one surface of the reservoir body; a plate-shaped heater which is formed on the outer wall surface of the sealing member in a set pattern; and an overcurrent prevention part which is connected to a separate electrode connected to the heater pattern. According to the present invention, the plate-shaped heater, which is formed on one surface of the reservoir body and is heated by applied power, maintains the temperature of the washer fluid at a set temperature or heats the washer fluid to a set temperature through a simple structure.
