Carlos Gustavo Tamm de Araújo Moreira (born 8 February 1973 in the city of Rio de Janeiro) is a Brazilian mathematician working on dynamical systems, ergodic theory, number theory and combinatorics. Moreira is currently a researcher at the Instituto Nacional de Matemática Pura e Aplicada (IMPA).
Moreira obtained his Ph.D. from the IMPA under the supervision of Jacob Palis in 1993, at the age of 20. He is a member of the Brazilian Academy of Sciences since 2008. In 2009 he was awarded the Award for his contributions to mathematics.
Moreira was an invited speaker at the International Congress of Mathematicians of 2014, in Seoul, South Korea and is a recipient of the 2010 TWAS Prize.
In June 2017 Moreira was invited to present a plenary speech on his research at the 2018 International Congress of Mathematicians in Rio de Janeiro, Brazil.