The race marked the competitive début of Pirelli's new hypersoft tyre compound.
Chassis updates
Following controversy over the use of winglets above halo-mounted rear view mirrors at the previous round in Spain, the FIA banned the winglets ahead of the race weekend.
Penalties
Romain Grosjean was handed a three-place grid penalty for causing a collision on the opening lap of the Spanish Grand Prix. Max Verstappen received a 5 place grid penalty for an unscheduled gearbox change, and a 10 place grid penalty for use of a third MGU-K, although this made no difference to his starting position, as he already was at the back of the grid.
Practice
was fastest across all three practice sessions, improving his time in each successive session. In FP3, Max Verstappen crashed heavily at the Turn 16, meaning his car was damaged beyond repair for qualifying.
Qualifying
was unable to compete in qualifying as his mechanics were unable to repair the car in time after a crash in the final practice session. Daniel Ricciardo set a new qualifying lap record to take pole position for the race. Red Bull capped both ends of the grid, Ricciardo starting first and Verstappen starting last. Pierre Gasly made Q3 for the second time, however his teammate, Brendon Hartley, after showing promise with P7 in FP3, qualified in P16 after being held up in traffic as well as being unhappy with the balance in his car.
Race
led going into the first corner with the top 6 staying in the same order. On lap 28, Ricciardo, still leading the race, complained of a loss of power to the team. Ricciardo was left to manage a wounded car for the remaining 50 laps of the race, with what was later revealed to be an MGU-K failure, and with only six out of eight gears functioning. Sergey Sirotkin was given a 10-second stop-go penalty after his tyres were not fitted to the car at the 3 minute signal. On lap 53 Fernando Alonso retired at Sainte-Dévote due to gearbox problems, his first retirement of the 2018 season. A virtual safety car came out on lap 70 when Charles Leclerc's left frontbrake disc failed just before the Nouvelle Chicane, causing him to crash into the back of Brendon Hartley. Both drivers were forced to retire due to damage. This was the first Monaco Grand Prix since 2009 where a safety car did not make an appearance, although there was a brief virtual safety car period.
Post race
After the raceHamilton and Alonso both complained that this was "one of the most boring races ever"; drivers were lapping several seconds a lap slower than they could have been to conserve tires and avoid making a second pit-stop. Alonso also pointed to the spread out field, "as there were barely any yellow flags or safety cars."
Classification
Qualifying
;Notes
– Romain Grosjean received a three-place grid penalty for causing a collision in the previous round.
– Max Verstappen failed to set a Q1 time within the 107% requirement and was allowed to start the race at the stewards' discretion. He also received a 15-place grid penalty: five place for an unscheduled gearbox change and ten place for use of a third MGU-K.
Race
;Notes
– Charles Leclerc and Brendon Hartley did not finish the Grand Prix, but were classified as they completed more than 90% of the race distance. Although Hartley completed his 70th lap before Leclerc, Hartley is classified behind Leclerc due to a 5-second time penalty for speeding in the pit lane.
