The aim of this experiment was to investigate how glossing influences second language (L2) reading comprehension in relation to text difficulty and the two local and global meaning representations. Fifty-eight undergraduate students were asked to read three easy, moderate, and difficult texts and, following each passage, answer twenty comprehension questions targeting local and global concepts in one of the two first-language-glossed and unglossed conditions. Half of the participants in each group were supposed to think aloud while reading. The results revealed a significant difference between the performance of glossed and unglossed groups on comprehension of local concepts in all three difficulty levels. However, the impact of glossing on comprehension of global concepts was significantly influenced by text difficulty. The qualitative analysis of think-aloud protocols suggested a substantial difference in glossing functionality on fluency between the easy and the difficult texts. Furthermore, it is suggested that revisiting the glossing effect in combination with text difficulty on the reading product and underlying processes might reconcile some divergent hypotheses on glossing impact on fluency.