Through reviewing hundreds of student attempts on hkimo+past+papers+senior+secondary, I have identified three fatal errors:

The HKIMO is a prestigious contest designed to identify and nurture mathematical talent. The Senior Secondary level is tailored for students in Forms 4 to 6 (Grades 10-12). Unlike typical school exams, the HKIMO emphasizes:

There are specific books available in Hong Kong bookstores (like Commercial Press or Swindon) that compile Olympiad problems.

HKIMO is part of a family of Olympiads. The Singapore International Math Olympiad Challenge (SIMOC) papers are very similar. Use them as proxies if Hong Kong-only papers are scarce.

Before diving into past papers, you must understand the battlefield. The HKIMO consists of two main rounds:

For Senior Secondary (S4-S6), the syllabus includes:

Past papers from the last 5 years show a consistent trend: 40% of the marks come from Algebra, 30% from Number Theory, and 30% from Geometry/Combinatorics.