The Rodovia dos Tamoios (official designation SP-099) is a highway in the Brazilian state of São Paulo.

The Rodovia dos Tamoios is a dual carriageway running from the city of São José dos Campos, located in the Paraíba River valley in the upper plateau of São Paulo down the Serra do Mar to the coastal lowlands of the city of Caraguatatuba, connecting to the Rodovia Rio-Santos (federal highway).

It was managed and maintained by the Department of Roads of the State of São Paulo (DER) until April 18, 2015.

The section crossing the Serra do Mar was a single lane road until 2022, turning into a dual lane with the inauguration of a new 22 km-long road for drivers heading uphill on the Serra do Mar towards São José dos Campos in 26 March 2022.

The project, that took seven years to complete, required the excavation of 1.7 million cubic meters of rock and the construction of six viaducts and four tunnels in an investment of over 3 billion reais.