The technical solution for reaching the object of this invention is as follows: a blue-ray photocuring 3D printing pen, comprising a casing, an ink cartridge located within the casing, a penpoint located on the head end of the ink cartridge and extending out the casing, a photosensitive resin placed within the ink cartridge. The blue-ray photocuring 3D printing pen further comprises a plurality of blue-ray LED arranged around the circumference of the penpoint. The photosensitive resin is capable of flowing out of the penpoint, and the blue-ray is configured to irradiate and solidify the photosensitive resin, wherein the wavelength of the blue-ray LED ranges from 465 nm to 485 nm.