Julien Simon-Chautemps (born 14 May 1978) is a French race engineer, currently employed by Sauber as race engineer for Marcus Ericsson. From 2007-2010 he was race engineer to Jarno Trulli at Toyota and Lotus. In 2011 he moved to Renault, and was engineer to Vitaly Petrov, Kimi Räikkönen, Pastor Maldonado, Romain Grosjean and Jolyon Palmer.
In 2017, Chautemps moved to Sauber.