Can glueball be created by electron-positron colliders? Since electrons and positrons are leptons, which don't experience strong interaction, and glueballs are unadulterated entities of quantum chromodynamics. Does that mean hadron colliders are better at finding glueballs?
 A: Electron positron colliders with enough energy generate hadrons. The possible candidates for glueballs are resonances of low enough energies to be accessible to e+e- colliders. One such candidate comes from the Babar experiment which is an e+e- collider experiment.

X(3020) observed by the BaBar collaboration is a candidate for an excited state of the 2-+, 1+- or 1-- glueball states with a mass of about 3.02 GeV/c^2.

The answer is no, hadron colliders are not better, in fact proton proton strong interactions create a complicated environment which is much harder to analyze.
The experiment designed to identify glueball resonances is  happening at an electron accelerator.

GlueX will be a particle physics experiment located at the Thomas Jefferson National Accelerator Facility (JLab) accelerator. Its primary purpose is to understand the nature of confinement in quantum chromodynamics by mapping the spectrum of exotic mesons generated by the excitation of the gluonic field binding the quarks. If successful, GlueX would be the first experiment to discover such exotic mesons, which have never before been observed. 

The electromagnetic interaction of the electron allows it to directly interact with a quark in clean calculable vertices, which allow the study of backgrounds and signal in a much cleaner way than in a hadron-hadron collision.
