To provide a camshaft fixing device for an engine capable of reducing vibration and noise generated by rotation of a camshaft by improving rigidity for fixing and supporting the camshaft and more easily enforcing disassembling/ assembling of the camshaft.

This device includes a cylinder head provided with many stably fixed grooves to rotate the camshaft and a full cam carrier which is fixed and coupled to/with the cylinder head to support a rotary motion of the camshaft stably fixed in the grooves of the cylinder head and is formed into an integral type so that a plurality of ribs corresponding to the grooves of the cylinder head may be connected at set intervals.