Within the last two decades, researchers have begun to investigate how L2 learners process syntactic, morpho-syntactic, and lexical information during the comprehension of L2 sentences. The present study aimed to add to research by investigating how L1 influences L2 processing of sentences indicating plurality in constructions involving numerals. More specifically, the research investigated whether Persian speaking low-proficient L2 learners of English showed L1 transfer effects performing a self-paced online reading task. To address this issue, employing the IBEX software, reaction times on critical regions and accuracy rates of learners' performance were measured on four types of structures (i.e., "Numeral + Count Noun," "Numeral + Classifier + Mass Noun," "Numeral + Classifier + Count Noun," and "Numeral + Non-referential Noun + Noun") and two sentence types ("ill-formed" vs. "well-formed"). Statistical analysis indicated the effect of both structure and sentence type on reaction times on the critical regions studied. Results also indicated traces of L1 effect in processing "Numeral + Classifier + Mass Noun" and "Numeral + Classifier + Count Noun" structures. Concerning the "Numeral + Count Noun" and "Numeral + Classifier + Non-referential Noun + Noun," no clear evidence for L1 transfer effect was observed. Further studies employing a larger sample size, investigating the issue at higher proficiency levels, and having native English speakers as control group are suggested.