Revenue rose to $20.26bn (Â£14bn) between January and March, from $17.26bn a year earlier.
But Alphabet's share price fell about 6% in after-hours trading, as the revenue figure fell short of analysts' expectations.
Net income for the quarter was $4.2bn, up from $3.5bn a year ago.
The earnings report came one day after the European Commission issued formal antitrust charges against Google over claims that it abuses the dominant market position of its Android operating system.
Google's advertising revenue jumped 16.2% in the first quarter to $18.02bn. The company said the number of ads, also known as paid clicks, jumped 29%.
But the average price of online ads, known as cost-per-click, fell 9% in the quarter.
Ruth Porat, chief financial officer at the parent company Alphabet, said the first quarter results represented a "tremendous start to the year", and that the company is "thoughtfully pursuing big bets and building exciting new technologies" which she hopes will put the company in a good position for long term growth.
Google embarked on a restructuring drive late last year and created a new parent company - Alphabet.
Under the rebranding, Google retained its best-known businesses, such as search, apps, YouTube and Android. Some of the newer entities, such as the investment and research divisions, the "smart-home" unit Nest, and the drone arm will be run under Alphabet.

Simon Dredge suffered life-threatening injuries in the crash on Wednesday.
He was travelling in the boat along with three other professional crew including his father Peter, a champion powerboat racer.
Powerboat company, Vector World said the boat was on its first test run when it overturned just after 08:20 BST.
A spokeswoman said: "We are encouraged to hear that Simon is stable and improving."
Peter Dredge, Simon Wood-Power, a powerboat racer and Lee Hurst, a powerboat engineer were all taken to Southampton General Hospital with non life-threatening injuries.
They have since been discharged.
Eyewitnesses described seeing the high-powered vessel come out of the water "like a rocket" before flipping over.
In a statement following the crash, Hampshire Constabulary said it appeared the powerboat "lost control" just before it collided with the Hamble Point cardinal mark.
The large metal buoy marks the entrance to the Hamble River.
A joint investigation into the crash is being carried out by Hampshire Police Marine Unit and the Marine Accident Investigation Branch.

The hosts lost both openers cheaply, as Nick Gubbins was caught off the bowling of James Tomlinson, and Sam Robson edged Tino Best to Jimmy Adams.
But Voges and Malan's 279-run stand put Middlesex firmly on top, before Malan edged Liam Dawson to slip for 147.
Voges remained unbeaten at the close on 128 alongside John Simpson (28) as Middlesex finished the day on 342-3.
Middlesex's third-wicket partnership leaves them in strong position to claim their first win in the County Championship this season, having drawn all six of their games so far.
Voges' ton, his first of the season, came off 200 balls, taking the former Australia batsman beyond 13,000 first-class runs in his career.
Malan was more aggressive in dismantling Hampshire's bowling attack, hitting 17 fours and two sixes before getting dismissed attempting to drive a Dawson delivery.
The visitors could take few positives from their performance, but they will remain hopeful of salvaging a draw from the game, with poor weather forecast for Tuesday's third day.
Alphabet - Google's parent company - has reported a 17% rise in quarterly revenue after strong advertising sales on mobile devices.
[NEXT_CONCEPT]
A teenager is "stable and improving" in hospital after the prototype powerboat he was training in crashed and overturned in the Solent.
[NEXT_CONCEPT]
Adam Voges and Dawid Malan both hit tons as Middlesex dominated Hampshire on day one at Merchant Taylors' School.