The USA Biology Olympiad, also known as USABO, is hosted by the Center for Excellence in Education (CEE). CEE is a nonprofit academic and educational organization founded in 1983. As the organizing committee of the USA Biology Olympiad, CEE selects and trains the U.S. national biology team each year to participate in the International Biology Olympiad (IBO).
In recent years, majors such as medicine, biomedical sciences, and biotechnology have become highly competitive choices at top U.S. universities. Strong performance in USABO can become an important advantage for students applying to these fields. As a result, USABO has become one of the most academically rigorous and influential STEM competitions in the United States, attracting more than 10,000 high school students every year.
USABO official website: https://www.usabo-trc.org/
USABO Scale and Award Difficulty
Each year, more than 10,000 students across the United States participate in USABO. Award winners may have the opportunity to receive invitations to top international science programs and competitions.
In the China region, the competition is administered by the BioOlympiad Initiative USA-China (BIOUS), organized by ASDAN. Awards are divided into four levels based on percentile ranking:
| Award | Percentile Requirement |
|---|---|
| Top Gold | Top 5% |
| Gold | Top 15% |
| Silver | Top 30% |
| Bronze | Top 45% |
Recent raw score cutoffs out of 50 have been approximately: Gold 40, Silver 33, Bronze 25.
Why USABO Is Worth Participating In
Like many high-quality international STEM competitions, USABO has a long history and a strong selection mechanism. It can directly demonstrate a student’s academic ability and subject excellence.
At the same time, USABO encourages students to explore advanced biology knowledge, much of which goes beyond the standard school curriculum. Preparing for the competition also helps students improve self-study skills, information-gathering ability, and academic discipline. In this sense, USABO preparation is a multidimensional process of growth.
Officially, USABO is open to high school students of any grade. However, because of its difficulty and selectiveness, students are advised to have a certain foundation in general biology. It is also helpful to have experience in biology competition courses or the ability to self-study college-level biology. Students should be prepared to spend enough time reading thousands of pages of materials and reference books. Most importantly, they need to have a genuine passion for biology.
USABO Rules and Format
USABO is an individual competition. The exam consists only of a written test, with no laboratory exam. Students need to complete 50 multiple-choice questions in 50 minutes. The exam is conducted entirely in English.
The 2026 China region exam took place on Saturday, April 4, 2026. The next season (2027) exam date will be announced later in 2026 through official ASDAN channels.
According to the official exam scope, USABO covers the following areas:
- Animal anatomy and physiology
- Cell biology
- Genetics and evolution
- Plant anatomy and physiology
- Ecology
- Animal behavior
- Biosystematics
- Neurobiology
- Bioinformatics
The Role of USABO in University Applications
Strong USABO results can strengthen applications to U.S. universities, especially for students applying to medicine, biology, biomedical science, biotechnology, and other STEM-related fields.
For students interested in biology or related disciplines, USABO has strong recognition and academic value. Awards can be listed directly in the Honors section of the Common Application and make compelling material for personal essays.
Three Keywords to Describe USABO
Broad coverage, fine details, and mental resilience.
Biology itself covers a very wide range of content. Each subfield also contains many smaller branches. Students may need to remember specific proteins, hormones, chemical substances, and biological terms. For example, when studying the citric acid cycle, students may need to remember how much ATP is produced at each step.
Because USABO covers broad content with detailed knowledge points, students need to maintain a strong mindset. They should not panic when they encounter unfamiliar topics. Mental resilience means staying calm when facing complex graphs, large tables, or long passages.
Key Topics, Difficulties, and Question Features
The exam covers cell biology, plant anatomy and physiology, animal anatomy and physiology, animal behavior, genetics and evolution, ecology, and biological classification.
One of the major focuses of USABO is biochemistry, especially the properties of the 21 amino acids, including whether they are acidic or basic, their charge status, and their chemical formulas.
Broad coverage: Memorized knowledge is often only a tool, not the final answer. Experimental design questions require students to draw on knowledge from multiple perspectives.
Fine details: Students need precise recall of specific biochemical facts and terminology to succeed on individual questions.
Mental resilience: Students need to stay calm when facing complex graphs, large tables, or long passages. If students prepare seriously, stay focused during the exam, and remain calm when facing difficult or unusual questions, their hard work is likely to pay off.
How to Prepare for USABO
Campbell Biology is one of the most comprehensive and widely used reference books for biology competitions. Students should plan their daily reading volume carefully. For students more comfortable reading Chinese, General Biology can be a useful starting point. It has broad coverage and is more accessible.
Recommended reading order:
- General Biology
- Campbell Biology
- More specialized books, such as Lehninger Principles of Biochemistry
Crash Course videos are also very useful for visual learning and memory reinforcement. Past papers should be used in the later stage of preparation. They are the best way to understand the real exam format and difficulty level.
Taking biology competition training courses can be very helpful. These courses usually cover biochemistry, plants, genetics, animal physiology, and other major areas comprehensively. Forming a study group with classmates can also be very effective. The key to staying consistent in USABO preparation is passion and persistence.
Students can use the glossary at the back of Campbell Biology to study difficult biological terms. Biology vocabulary often contains clear roots and prefixes. Repeated reading in context can make memorization stronger and reduce confusion between similar terms.
Final Suggestions
For students earlier in their high school journey, studying biology competition content first can be very useful, and there is usually enough time to build a strong foundation.
For students closer to exam time, it is more efficient to focus mainly on Campbell Biology. Before the exam, students should memorize key terms and review high-frequency topics, including plant anatomy, the stages of mitosis and meiosis, animal classification, and amino acid properties and abbreviations.