An openable roof window includes: a window panel configured to be slidable along a guide rail to selectively open and close an opening in a roof and tiltable relative to a base frame; a slider having a pin and driven by a drive device to slide along the guide rail; an engagement structure that selectively engages the slider with the window panel such that they are unmovable relative to each other in a direction along the guide rail; and the engagement structure includes a stay fixedly secured to the window panel and having a cam groove formed therein, the cam groove engaging the pin of the slider and having a shape defined such that, when the engagement structure does not engage the slider with the window panel, the window panel is caused to tilt as the slider moves relative to the stay as a result of sliding of the slider along the guide rail.