This mixed method study aimed to examine if, and then potentially how, the level of preservice teachers' metacognitive awareness (MA) influences their reflective thinking on their teaching practicum experiences in the context of web-based portfolio construction. Data sources included two sets of reflection task responses and a Likert-type metacognitive awareness inventory. Data from these sources were coded and analyzed using quantitative and qualitative methods. The total number of high-level reflective thinking indicators produced by the preservice teachers with high MA was notably higher than those generated by the preservice teachers with low MA. A Wilcoxon-Mann-Whitney test revealed a statistically significant difference between the scores of high-level reflective thinking indicators exhibited by the preservice teachers with high MA and low MA. In addition, a statistically significant moderate relationship was found between the participants' total MA scores and their high-level reflective thinking scores. Findings suggested that when the participants were good at managing the three metacognitive processing skills, namely monitoring, evaluation, and planning, they more frequently exhibited the high-level reflective thinking indicators.