The utility model provides an insulating fiber groove of fire prevention, including groove, lid and buckle, the groove cross section comprises bottom plate and recess shape pterygoid lamina for recess shape, buckle, the lid is laminated structure, and the groove comprises the end and the pterygoid lamina of perpendicular its both sides, the pterygoid lamina edge is equipped with and is on a parallel with the edge at the end the outside flange of pterygoid lamina, flange thickness with pterygoid lamina thickness is the same, and the width is less than the pterygoid lamina, the pterygoid lamina section thickness with the base thickness degree is the same, the pterygoid lamina with end coupling part is the right angle, the groove includes sharp groove and arc wall two parts, constitution snake -shaped structure is connected in turn to straight line groove and arc wall, the utility model has the advantages of simple structure, this fiber groove only includes groove, lid and buckle three, and it is convenient to install in dismantling, only need during the fiber groove installation approximately to align with the groove, with the buckle chucking can, the utility model discloses special snakelike tendency appearance plays important effect to aspect controls such as the creepage distance of optic fibre, insulating length.