TIMSS 2019 is the seventh cycle of the IEA Trends in International Mathematics and Science Study (TIMSS). The study was initiated in February 2017 at the first national research coordinators meeting. The Framework review and instrument development work was carried out in 2017. The field test was conducted in March 2018. The data collection for the main survey was predominantly carried out in October 2018 in the Southern Hemisphere and April 2019 in the Northern Hemisphere. The international reports will be released in December 2020.
TIMSS 2019 marked the debut of eTIMSS, an electronic version of TIMSS. More than half of the countries participating administered the assessment via computer, while the rest of the countries administered TIMSS using paper-and-pencil tests, as in previous assessments.
The following education systems will participate in this round of TIMSS:
| Albania | Hungary | Norway |
| Armenia | Islamic Republic of Iran | Oman |
| Australia | Ireland | Pakistan |
| Austria | Israel | Philippines |
| Bahrain | Italy | Poland |
| Belgium | Japan | Romania |
| Bosnia and Herzegovina | Jordan | Portugal |
| Bulgaria | Kazakhstan | Qatar |
| Canada (with Ontario and Quebec as benchmarking systems) | Kosovo | Romania |
| Chinese Taipei | Kuwait | Russian Federation (with Moscow as a benchmarking system) |
| Croatia | Latvia | Saudi Arabia |
| Cyprus | Lebanon | Serbia |
| Czech Republic | Lithuania | Singapore |
| Denmark | Republic of North Macedonia | Slovak Republic |
| Egypt | Malaysia | South Africa |
| England | Malta | Spain (with Madrid as a benchmarking system) |
| Finland | Montenegro | Sweden |
| France | Morocco | Turkey |
| Georgia | Netherlands | United Arab Emirates (with Abu Dhabi and Dubai as benchmarking systems) |
| Germany | New Zealand | United States |
| Hong Kong SAR | Northern Ireland |