ZnO nanoneedles were synthesized via thermal evaporation method without any catalyst. Scanning electron microscopy and transmission electron microscopy investigations showed that these products presented a nanoneedle structure. To enhance the field emission (FE) properties of screen printed ZnO nanoneedles, a given amount (0.05 g) carbon nanotubes (CNTs) mixed with (0.5 g) ZnO nanoneedles paste via screen printed method and heat-treatment at (600 degrees C, 500 degrees C and 450 degrees C) was presented. The CNTs-mixed ZnO nanoneedles heat-treated at 450 degrees C had the lowest turn-on field of 3.75 V/mu m, highest field emission current of 0.16 mA at 7.5 V/mu m and highest beta of 830. An efficiency FE enhancement of 450 degrees C sample was attributed to melioration of conductance between ZnO nanoneedles and ITO surface by CNTs. (C) 2011 Elsevier B.V. All rights reserved.