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Red Palm Weevil (RPW), Rhynchophorus ferrugineus Oliv. (Col.: Dryophthoridae), is a key pest of date palm in Asia, North Africa and Spain. A field study was conducted in south eastern Iran to find the effect of odor sources in traps on RPW behavior. This study consisted of four experiments; each included four treatments (odor sources) and eight replications. Each experiment was repeated 4 times (i.e. four different distances between odor sources (treatments) were considered: 0, 0.5, 2 and 5 meters). In each treatment, two traps were used. The treatments were as follows: 1) one trap included two pheromones and the other trap included two pieces of plant tissue, 2) both traps included one pheromone along with one piece of plant tissue, 3) both traps included one pheromone, and 4) both traps included one piece of plant tissue. Overall, much less RPWs were caught in the traps of treatments 3 and 4 (baited with only the pheromone or the plant bait) than in the traps of treatments 1 and 2 (baited with pheromone and plant tissue) evidencing the phenomenon of synergy, previously reported. The Results of analysis of variance of total catch of traps, at all between-trap distances indicated that there was significant difference among treatments. In all experiments, traps that contained just palm tissue had the least catch rate. The RPW distinguished pheromone from plant odor when both sources were separated by less than 5 m. At distances of 5 m, attractancy of plant odor was similar to pheromone attractancy. Our results suggest that each of the chemical cues probably induce a different behavioral process. Probably, pheromone would attract RPWs from a distance, making them fly towards the pheromone sources (traps) while the plant odor would arrest flight and induce landing and local search by walking for palm tissue, resulting in entry into traps.