Having started strongly to combat any threat from fellow front-row starter Pascal Wehrlein, Evans held the lead through the race's first third, dictating the pace as the frontrunners elected to save energy in the early period.
But as the race's action slowly began to spool up, Evans then came under threat from Wehrlein, who considered a move at the Nouvelle Chicane, but decided against it.
This came at the point where a number of drivers elected to expend their first attack mode activations, where Jean-Eric Vergne was the first among the frontrunners to take the 250kW power mode.
Thus, the DS Techeetah was in position to assume the lead when Evans and Wehrlein claimed their own attack modes, while Wehrlein eventually cleared the polesitter as the Kiwi began to struggle compared to his rivals on energy available.
Evans then lost a further place to Vandoorne, while Wehrlein then moved past Vergne to pick up the lead of the race with attack mode in his pocket.
But Wehrlein began to slow, gifting the lead to Vergne, who picked up his second dose of attack mode on the following lap - which would prove to be to his detriment.
Taking the wide line at Casino Square, Vergne had no option to let Vandoorne and Evans pass, and his misery was compounded when Wehrlein's Porsche stranded post-tunnel produced a full-course yellow to ensure Vergne's useable attack mode would elapse.
No sooner had Wehrlein's slowing car peeled off into the service road at the Nouvelle Chicane, allowing Vandoorne to pick up attack mode with no loss in position on lap 19, Andre Lotterer's wall-bound Porsche prompted the arrival of the safety car.
Lotterer was attempting to hold position from Oliver Rowland at Sainte Devote, and the Brit's ambitious lunge not only resulted in his Mahindra hitting the wall, but also left Lotterer with nowhere to go except the Tecpro barrier.
With the race resuming on lap 21, Vandoorne hardly had to look back and, although Evans was able to eat into a gap that had previously stood at three seconds, the Belgian crossed the line to secure victory - and the championship lead.
Evans overcame his earlier energy issues, partially exacerbated by being out in the lead, to build a two-second lead over Vergne and take a conciliatory second place finish.
Vergne completed the podium following his earlier spell in the lead, although was under heavy assault from Robin Frijns by the end of the race as the Envision driver made some choice attack mode activations to move forward from seventh on the grid.
Antonio Felix da Costa overcame a poor qualifying to sit close to Frijns' tail by the end, as the Portuguese driver was unable to deliver on the promise of practice and instead was turfed out in group qualifying.
Da Costa's second attack mode activation allowed him to clear Lucas di Grassi, who was ultimately unable to resist the Season 6 champion's advances despite a stern defence.
Nick Cassidy collected seventh after a typically swashbuckling drive, capitalising on using his attack mode early and then being in position to take advantage when Nissan e.dams' Maximilian Guenther began to run dry on useable energy at the race's climax.
Sebastien Buemi converted a last-place start to salvage points for Nissan in eighth place, crossing the line a mere 0.047s clear of Avalanche Andretti's Jake Dennis.
Nyck de Vries ensured Mercedes bookended the scorers with 10th place, crossing the line a second ahead of Alexander Sims - who continues to wait for his first point of the season.
Edoardo Mortara was on course for points before an unspecified issue forced the Venturi driver to pit and retire from the race.
Formula E Monaco E-Prix - Race results
| Cla | Driver | Team | Laps | Time | Gap | Interval |
|---|---|---|---|---|---|---|
| 1 |  Stoffel Vandoorne |  Mercedes | 30 | 51'12.473 | ||
| 2 |  Mitch Evans |  Jaguar Racing | 30 | 51'13.758 | 1.285 | 1.285 |
| 3 |  Jean-Eric Vergne | Techeetah | 30 | 51'15.766 | 3.293 | 2.008 |
| 4 |  Robin Frijns | Virgin Racing | 30 | 51'15.940 | 3.467 | 0.174 |
| 5 |  Antonio Felix da Costa | Techeetah | 30 | 51'16.425 | 3.952 | 0.485 |
| 6 |  Lucas di Grassi |  Venturi | 30 | 51'20.606 | 8.133 | 4.181 |
| 7 | Nick Cassidy | Virgin Racing | 30 | 51'27.746 | 15.273 | 7.140 |
| 8 |  Sébastien Buemi | DAMS | 30 | 51'30.246 | 17.773 | 2.500 |
| 9 | Jake Dennis |  Andretti Autosport | 30 | 51'30.293 | 17.820 | 0.047 |
| 10 | Nyck de Vries | Mercedes | 30 | 51'30.756 | 18.283 | 0.463 |
| 11 | Alexander Sims |  Mahindra Racing | 30 | 51'31.823 | 19.350 | 1.067 |
| 12 | Dan Ticktum | NIO Formula E Team | 30 | 51'32.229 | 19.756 | 0.406 |
| 13 | Sergio Sette Camara | Dragon Racing | 30 | 51'35.367 | 22.894 | 3.138 |
| 14 |  Antonio Giovinazzi | Dragon Racing | 30 | 51'35.460 | 22.987 | 0.093 |
| 15 | Oliver Turvey | NIO Formula E Team | 30 | 51'35.671 | 23.198 | 0.211 |
| 16 | Oliver Askew | Andretti Autosport | 30 | 51'35.905 | 23.432 | 0.234 |
| 17 | Maximilian Gunther | DAMS | 30 | 51'52.141 | 39.668 | 16.236 |
| Edoardo Mortara | Venturi | 23 | 40'23.244 | 7 Laps | 7 Laps | |
| Oliver Rowland | Mahindra Racing | 18 | 30'28.714 | 12 Laps | 5 Laps | |
| Andre Lotterer | Porsche Team | 18 | 30'28.955 | 12 Laps | 0.241 | |
| Pascal Wehrlein | Porsche Team | 15 | 24'11.896 | 15 Laps | 3 Laps | |
| Sam Bird | Jaguar Racing | 7 | 11'38.444 | 23 Laps | 8 Laps | |
| View full results | ||||||
