This study examined the metacognitive developmental patterns of Hong Kong school students. Students rated their own metacognitive competencies by responding to an inventory of six motivational- and cognitive-metacognitive subscales. Results showed that students' metacognitive competencies decreased with age--from primary 4 (age 9) to secondary 5 (age 17)--with a sharp decline noticeable at the primary/secondary school transition. Age had a more powerful effect than gender on students' perception of their metacognitive competencies. This decreasing pattern of Hong Kong students' metacognitive competencies is contrary to the developmental trends found in Western countries. However, the comparatively high academic performance of Hong Kong students also suggests some different recommendations about student learning. Inventory of metacognitive components is appended. (Contains 3 tables and 3 figures.)