A strong daylight-fluorescent boron dipyrromethene (BODIPY) derivative 1 has been synthesized for the visual and colorimetric detection of cyanide anion in solution. BODIPY 1 shows a glow characteristic of daylight-fluorescent material since emitted fluorescent light has been added to the simple reflection light under daylight illumination. This green daylight fluorescence is diminished upon interaction with cyanide anion, resulting in a highly selective and sensitive naked-eye detection of cyanide anion over other common anions.