Sainz was due to start from 12th position after a disappointing qualifying on Friday in which he missed the cut to Q3 by 0.031s.
But just an hour before the race, the Ferrari team announced that the Spaniard would not make the start at all, after encountering a fuel system issue on the car.
Ferrari's mechanics frantically worked to get Sainz's SF-23 ready to go to the grid, but ultimately found the problem could not be remedied in time for the race, which starts at 8pm local Qatar time.
In a brief statement the Italian team said: "Due to a fuel system issue on his car, Carlos will not take part in the Qatar GP."
Ferrari's Qatar hopes are now solely pinned on his team-mate Charles Leclerc, who will start the race at the Losail International Circuit from fifth on the grid, with recently crowned triple world champion Max Verstappen leading the field from pole.
No additional time penalty for Perez
Elsewhere, Sergio Perez will start from the pitlane after his crash in Saturday's sprint race, in which he tangled with Alpine's Esteban Ocon and Haas veteran Nico Hulkenberg.
Perez's primary chassis was damaged beyond repair, forcing the Milton Keynes outfit to build up a spare chassis overnight. It also took the opportunity to change the Mexican's full Honda power unit as he was due a pitlane start anyway due to parc ferme breaches.
Perez was at risk of copping an additional time penalty during the race after the team was alleged to have built a third car by the FIA's technical team. A similar offence cost Williams' Logan Sargeant an additional 10-second penalty at the recent Japanese Grand Prix at Suzuka.
But the stewards concluded that because Red Bull had dismantled Perez's original car to the point where it no longer met the criteria of a "car", at no point did it have two cars available for Perez.
The stewards wrote: "The Stewards acknowledge the fact that neither Article 27.1 nor Article 27.2 was breached as the competitor at no time had more than two cars available for use as no more than two assemblies comprising a survival cell as defined in Article 12.1 of the Technical Regulations and additional components were used at the same time."
They added that by fully disassembling its first chassis Red Bull circumvented the regulations as they were intended. And while the team did nothing wrong, they recommended that the definition of what constitutes a spare car be clarified at the next Sporting Advisory Committee.
"The Stewards note that the way Article 27.2 was interpreted by the competitor concerned, whilst not breaching the regulations, might not be fully in line with the intention of the relevant regulation and therefore recommend that the issue will be further discussed and clarified in the Sporting Advisory Committee."