A new type of 3D printing process is introduced. The printing mechanism is based on material jetting process by inkjet-printing head to eject and deposit a photopolymer ink as the 3D object building material. The existing material jetting 3D printer adopted multi nozzle piezo-electrical print head. The piezo ink jet head requires complicated head structure, ink supply and maintenance system. The printing area should be large because of wide area of printing head and it causes that the 3D printing machine should be large and expensive for a commercial purpose only. In this study, Thermal ink jet head is applied to the print head for 3D printing process. The thermal head has low cost and compact printing mechanism but it is hard to apply photo polymer ink of material jetting process for jetting fluid because the thermal ink jet head fires the ink droplet by boiling mechanism. The specific building material for jetting in thermal head is applied and a 3D printing process is investigated for stable ejection and deposition on the substrate for building 3D object. The droplet volume of print head is under 20 pico-litters and ejection frequency is 2 kHz and the thickness of single layer deposited for building object is more than 10 micro-meters. The 3D printing system is fabricated and the hollow cylindrical object with high aspect ratio is successfully built and printing process is verified.