An ink jet print head suitable for high-density printing. The ink jet print head comprises a plurality of nozzles for ejecting an ink, ink chambers, for passage and pressurization of the ink, communicating with the nozzles, and pressurizing means for creating a change in volume of the ink in the ink chamber to eject the ink through the nozzles. The ink chamber comprises a base plate member comprised of a transparent substrate having a predetermined form and dimension, a base wall member made of a material impermeable to light, the base wall member being provided above the base plate member in a pattern form according to the form of the ink chamber, and a partitioning member provided, above the base plate member, in areas not occupied by the base wall member. The partitioning member is formed from a partitioning member-forming, photosensitive material by photolithography using the base wall member pattern as a mask. A process of producing the above ink jet head is also disclosed.