Thiemo de Bakker (born 19 September 1988) is a Dutch tennis player, who is currently ranked 63rd in the world, and is the top ranked Dutch tennis player.
De Bakker finished 2006 as the ITF Junior Champion, after having won the Boys' Singles title at the 2006 Wimbledon Championships.
De Bakker received a wild card into the ATP Amersfoort event in July 2006 and defeated top 100 and French Open Quarterfinalist Julien Benneteau in the 1st round, winning in straight sets 6–3 6–3. In the 2nd round he faced Frenchman Marc Gicquel and lost in 3 sets, 6–4 3–6 2–6. As he was the reigning Junior Champion, De Bakker received a wild card into the main draw of the 2007 Wimbledon Championships, where he would lose in 5 tight sets to qualifier Wayne Arthurs, 7–6, 7–6, 6–7, 4–6, 4–6. In October 2006, De Bakker won his first senior international title in a Futures event in Albufeira, Portugal, where he beat Briton Morgan Phillips in the final 7–6 6–4. This was followed by another win in a Futures tournament two weeks later in San Miguel, Portugal. He reached a career high ATP ranking of 228 on 25 August 2008.