Iannone led from start to finish having started from pole position and he was a massive 2.7s clear after only three laps.
He stretched out his lead to almost seven seconds before easing off in the final stages to win by a comfortable 2.764s from Sergio Gadea.
The 20-year-old, who has now won five world championship races, said: “Although I was out in front on my own it was still a difficult race. It was hard to concentrate a little but this class is so close that when you have a small advantage you have to make it count. It is not easy when you see the standard of the riders behind me but this is a great victory and gives me a lot of confidence for the rest of the season.”
Iannone might have made the fight for victory non-existent with an impressive display that moved him into the top five in the overall standings.
But behind him the action was typically frantic.
French rider Jules Cluzel was leading the charge when he suffered a massive crash on lap five when he was lying in second place.
He walked away unhurt but is the second race in succession that Cluzel has crashed out of a podium finish.
An early eight-rider battle for the podium quickly became just five as early challenger Alex Debon faded badly to finish in tenth place.
That left championship leader Toni Elias, Gadea, Simone Corsi, Gabor Talmacsi and Qatar winner Shoya Tomizawa in a thrilling fight for second.
Talmacsi was unable to keep the pace and he eventually had to settle for seventh having finish nearly 3.5s away from the top six. The former world 125GP champion had been as high as second in the early stages.
Gadea eventually won the battle for second after a nail-biting sprint to the finish line.
Home favourite Corsi held second on the final but was unable to keep Gadea at bay, the Spaniard taking second by just 0.035s.
Speaking after his maiden Moto2 podium Gadea said: “I tried that move on Corsi on the lap before so knew I could make it work. I’m really enjoying Moto2 and I’m not so far behind in the championship now.”
Corsi was third having denied Swiss rider Thomas Luthi his podium by just 0.015s.
Corsi cemented his place in third in the championship with his second consecutive podium and he said: “I am really happy with this result because I closed the gap on Elias and Tomizawa at the front of the championship. The bike worked really well today and it was really good fun to be able to overtake so many riders.
Elias had to settle for fifth having been surprisingly unable to sustain a late attack for the top three.
The Spaniard though, riding the Gresini Moriwaki bike, was still able to extend his series lead to 19-points over Japanese rider Tomizawa.
Tomizawa finished sixth and just 0.422s adrift of Elias as he too failed to keep his pace in the decisive final moments.
British rider Scott Redding had another tough weekend. The Marc VDS Racing rider broke into the top 20 in the early stages having started in a lowly 28th on the grid but he was unable to keep his pace and he finished 21st, nine places behind team-mate Hector Faubel.
1 25 29 Andrea IANNONE ITA Fimmco Speed Up Speed Up 160.8 41’05.374
2 20 40 Sergio GADEA SPA Tenerife 40 Pons Pons Kalex 160.7 +2.764
3 16 3 Simone CORSI ITA JIR Moto2 Motobi 160.7 +2.799
4 13 12 Thomas LUTHI SWI Interwetten Moriwaki Moto2 Moriwaki 160.7 +2.814
5 11 24 Toni ELIAS SPA Gresini Racing Moto2 Moriwaki 160.6 +3.404
6 10 48 Shoya TOMIZAWA JPN Technomag-CIP Suter 160.6 +3.826
7 9 2 Gabor TALMACSI HUN Fimmco Speed Up Speed Up 160.4 +7.209
8 8 72 Yuki TAKAHASHI JPN Tech 3 Racing Tech 3 160.3 +8.377
9 7 60 Julian SIMON SPA Mapfre Aspar Team Suter 160.3 +8.584
10 6 6 Alex DEBON SPA Aeroport de Castello – Ajo FTR 160.3 +8.931
11 5 15 Alex DE ANGELIS RSM RSM Team Scot Force GP210 160.2 +9.149
12 4 55 Hector FAUBEL SPA Marc VDS Racing Team Suter 160.2 +9.991
13 3 25 Alex BALDOLINI ITA Caretta Technology Race Dept I.C.P. 160.0 +12.219
14 2 65 Stefan BRADL GER Viessmann Kiefer Racing Suter 159.6 +19.110
15 1 10 Fonsi NIETO SPA Holiday Gym G22 Moriwaki 159.6 +19.680
16 77 Dominique AEGERTER SWI Technomag-CIP Suter 159.5 +19.994
17 17 Karel ABRAHAM CZE Cardion AB Motoracing FTR 159.2 +24.969
18 44 Roberto ROLFO ITA Italtrans S.T.R. Suter 159.2 +25.769
19 19 Xavier SIMEON BEL Holiday Gym Racing Moriwaki 158.8 +31.094
20 68 Yonny HERNANDEZ COL Blusens-STX BQR-Moto2 158.8 +31.171
21 45 Scott REDDING GBR Marc VDS Racing Team Suter 158.4 +37.770
22 71 Claudio CORTI ITA Forward Racing Suter 158.3 +39.183
23 53 Valentin DEBISE FRA WTR San Marino Team ADV 158.3 +39.405
24 41 Arne TODE GER Racing Team Germany Suter 158.2 +40.613
25 21 Vladimir LEONOV RUS Vector Kiefer Racing Suter 158.1 +43.358
26 9 Kenny NOYES USA Jack & Jones by A.Banderas Promoharris 158.0 +43.997
27 8 Anthony WEST AUS MZ Racing Team MZ-RE Honda 157.4 +53.748
28 59 Niccolo CANEPA ITA RSM Team Scot Force GP210 157.4 +54.387
29 76 Bernat MARTINEZ SPA Maquinza-SAG Team Bimota 157.2 +57.035
30 88 Yannick GUERRA SPA Holiday Gym G22 Moriwaki 157.1 +58.612
39 Robertino PIETRI VEN Italtrans S.T.R. Suter 158.3 3 Laps
14 Ratthapark WILAIROT THA Thai Honda PTT Singha SAG Bimota 159.6 5 Laps
63 Mike DI MEGLIO FRA Mapfre Aspar Team Suter 159.2 6 Laps
61 Vladimir IVANOV UKR Gresini Racing Moto2 Moriwaki 159.2 6 Laps
35 Raffaele DE ROSA ITA Tech 3 Racing Tech 3 158.9 10 Laps
75 Mattia PASINI ITA JIR Moto2 Motobi 157.7 14 Laps
16 Jules CLUZEL FRA Forward Racing Suter 159.6 17 Laps
80 Axel PONS SPA Tenerife 40 Pons Pons Kalex 157.2 17 Laps
96 Anthony DELHALLE FRA Blusens-STX BQR-Moto2 154.2 18 Laps
52 Lukas PESEK CZE Matteoni CP Racing Moriwaki 154.6 19 Laps
5 Joan OLIVE SPA Jack & Jones by A.Banderas Promoharris 0 Lap
Source | MCN