The utility model discloses a multifunctional safety cap that can assemble, include the cap body, cooling subassembly, hindbrain support and protect the mesh subassembly, offer the first hole that isused for installation cooling subassembly on the cap body, set up the second hole on the cap body, be provided with the link that can insert the second hole on the hindbrain support, it connects on the cap body to protect the second draw -in groove that the mesh subassembly passes through on the cap body, the utility model discloses a safety helmet can be realized comparing in the more comprehensive cephalic protection of existing product, including cephalic protection, eye protection and respiratory protection, also can make things convenient for the workman to carry out work by the requiredaccessory in montage field, if illumination and communication, thereby each function block can be applicable to multiple construction environment according to the demand flexible package, satisfies more diversified demand, each function block is even reasonable in distribution around the cap body, enables the safety helmet and has given play to better combination efficiency.