The USA Biology Olympiad, for China’s brightest students.
The China-region exam uses the same papers and judging standard as USABO — 50 questions, 50 minutes, sat in your school, with national awards by percentile.
A world-standard test of biology
The USA Biology Olympiad (USABO) is the premier biology competition of the Center for Excellence in Education (CEE), reaching roughly 10,000 students a year. In China, students sit the equivalent Open Exam — the same questions, the same judging standard — and earn national awards ranked by percentile.
It rewards genuine understanding across cell and molecular biology, genetics, plant and animal physiology, ecology and evolution — not memorisation.
From one exam to the world stage
The full USABO pathway runs in four stages. In China, students enter through the Open Exam (BIOUS) and earn China-region awards; the Semifinal and National Finals are the United States team-selection path.
Open Exam
50 multiple-choice questions in 50 minutes, sat in your school. This is the China-region exam.
Semifinal Exam
The top 10% (US citizens and residents) advance to a longer, harder paper.
National Finals
The top 20 meet at a host university for a 12-day residential round with lab practicals.
International Biology Olympiad
A four-student national team represents the USA at the IBO (2026: Vilnius, Lithuania).
BioOlympiad Initiative USA–China
The China region is run independently by ASDAN under the name BIOUS. It uses USABO’s own papers and judging standard, with its own registration, schedule and award tiers for students in China.
Sitting BIOUS lets students measure themselves against the same benchmark as their peers worldwide — without leaving their school.
Explore the China region →What the USABO gives you
A world-standard benchmark
Measured against USABO’s real papers and judging — an honest read of where you stand.
Real biology, in depth
Cells and molecules, genetics, physiology, ecology and evolution — understanding, not recall.
A signal for admissions
A recognised academic distinction that strengthens applications to selective universities.
A clear pathway
From a single exam toward the International Biology Olympiad — one step at a time.
China-region awards, by percentile
Recent raw-score cutoffs (out of 50): Gold 40 · Silver 33 · Bronze 25. Exact thresholds are published each season.
Everything you need for the USABO
About
USABO, CEE and the path to the International Biology Olympiad.
Learn more →Competition
Exam structure, eligibility, awards and the route to the IBO.
See details →Exams & past papers
Format and topics, plus 20+ years of Open Exam papers.
Practise →Resources
Recommended textbooks, study guides and prep advice.
Prepare →Registration
Eligibility, deadlines, fees and how to register in China.
How to enter →Winners
Cutoff scores, results and where past students went on.
View results →One exam. Deep preparation.
A single 50-question paper measures real biology — cells and molecules, genetics, plant and animal physiology, ecology and evolution. Our archive of past Open Exams from 2003 onward is the deepest practice library in China.
Exam format & past papers →
Recommended reading
Full reading list →
Common questions
Who can take the USABO in China?
High-school students in China, sitting the exam at a partnering school. The exam is taken on paper; an online option may be available on request.
What is the exam format?
One Open Exam: 50 multiple-choice questions in 50 minutes, in English. There is no negative marking.
How do Chinese students participate?
Through the independent China region, BIOUS, run by ASDAN — using USABO’s own papers and judging standard, with China-region registration and awards.
What awards can I earn?
China-region awards are given by percentile: Top Gold (top 5%), Gold (top 15%), Silver (top 30%) and Bronze (top 45%), plus regional honours.
How should I prepare?
Work through past Open Exams from 2003 onward and study core texts such as Campbell Biology. See the resources page for a full plan.
When is the next exam?
The 2026 Open Exam was held in April 2026. Registration for the 2027 season opens later in 2026 — exact China-region dates are announced each season on the registration page.
Talk to a USABO advisor
Scan to reach our advisors, or message us via the WeChat QR code.