Ultra-hard film materials such as chemical vapor deposited (CVD) diamond are uniquely qualified for applications where superior tribological and electronic properties are required. Patterning of the film materials is essential to produce functional micro devices. Conventional lithography-based chemical etching is difficult or impossible on the ultra-hard diamond film materials, which have a high chemical resistance. Investigations on maskless patterning of the CVD diamond film are presented. Focused excimer laser pulses are used for dry etching on the film materials, and a micro computer numerical control (micro-CNC) stage is used for patterned translation of a target. The laser ablation of CVD diamond is observed to set up relationships among the processing parameters, such as the gas processing environments, the laser energy fluence and the number of laser pulses. The extent of the ablation-induced plasma is observed by time integrated image capturing. A cell-patterned structure, fabricated by the innovative maskless process, is presented for discussion.