The Belgian rider attacked on the fourth climb of the Cauberg with three kilometres remaining and kept fellow Belgian Jelle Vanendert and Simon Gerrans at bay for victory.
"I went for it at the steepest part and was happy I could hold on to my lead," said Gilbert.
"This was a particularly emotional win for me. My wife and my kids were here for the first time in two years. So to have won will be something they will never forget. I have been dreaming of this."
The day’s breakaway formed immediately as Pim Ligthart headed an eight-strong group before Christophe Riblon and Rory Sutherland moved through to join as the leaders amassed an advantage verging on 15 minutes.
Gilbert’s BMC outfit ensured the gap remained manageable before riders stared to drop off the front pack and the peloton closed in.
A series of attacks from the main bunch signalled an increase in tempo and the field eventually came together with seven kilometres remaining.
Gilbert attacked as the fourth circuit drew to a close and amassed a healthy lead – enabling him to slow in the closing stages and sit upright as he crossed the line.
1. Philippe Gilbert (Belgium / BMC Racing) 6:25:57"
2. Jelle Vanendert (Belgium / Lotto) +5"
3. Simon Gerrans (Australia / Orica) +6"
4. Alejandro Valverde (Spain / Movistar)
5. Michal Kwiatkowski (Poland / Omega Pharma - Quick-Step)
6. Simon Geschke (Germany / Giant) +10"
7. Bauke Mollema (Netherlands / Belkin)
8. Enrico Gasparotto (Italy / Astana)
9. Daniel Moreno (Spain / Katusha)
10. Yukiya Arashiro (Japan / Europcar) +12"
- Sports & Recreation
- Simon Gerrans
- Jelle Vanendert
- Christophe Riblon