A new natural surface modified nanoclinoptilolite (NCP) was prepared and applied as an efficient catalyst for the cyclotrimerization of acetophenones to obtain 1,3,5-triarylbenzenes. The results showed that the efficiency of this catalytic system was enhanced due to the surface modification by hexadecyltrimethylammonium bromide (HDTMA-Br). This proposed protocol brings about significant economic and environmental advantages, such as operational simplicity, short reaction time, mild reaction conditions, good reaction yield, and high recyclability of the catalyst. Furthermore, the only side product of the reaction is water, which makes this methodology an environmentally friendly process.