This device for heating a washer fluid is provided with a container that accommodates the washer fluid, a lid which is attached to a first end of the container and which faces the space accommodating the washer fluid, a heating means which is attached at the base end to the lid and which extends towards the accommodation space, and an outflow pipe which is arranged in the accommodation space and which has an outlet through which the washer fluid in the accommodation space exits. In the outlet of the outflow pipe, the space formed between the horizontal plane passing through the outlet and the inner wall surface of the second end of the container, opposite of the first end, is 10% or more of volume of the container space.