The wall-number-selective growth of vertical carbon nanotube (CNT) arrays is achieved by the combination of block copolymer lithography and plasma enhanced chemical vapor deposition of CNTs, and the field emission properties were measured as a function of wall-number, length, density and doping concentration of CNT arrays. Block copolymer lithography is an attractive nanopatterning method for generating a uniform catalyst particle arrays for carbon nanotube growth. In this work, highly uniform nanopatterned iron catalyst arrays were prepared by tilted evaporation through block copolymer nanotemplates, and the sub-nanometer-scale tunability of catalyst particles enabled the excellent controllability of the wall-number and density of the CNT arrays. Moreover, the use of ammonia in the growth of CNT arrays ensured that the CNTs were nitrogen doped, and the doping concentration of nitrogen can be adjusted by controlling the flow rate of ammonia gas. Substitution of a carbon in a CNT wall with a more electron-rich nitrogen atom provided additional electrons and enhanced the conductivity of the nanotubes. With the excellent controllability of CNT arrays, we investigated the field emission properties of the grown CNT arrays. Wall-number, length, density and the doping concentration of CNT arrays were changed independently to investigate their effect on the field emission properties. Therefore, superior field emission performance of CNT arrays was acquired by controlling the physical and chemical parameters of CNT arrays.