* Austerity steps weakening growth since early 2015

* Analysts think Q2 data may ultimately be revised lower

* Imports, other indicator show non-oil sector struggling

* Cuts to public sector allowances announced this week

By Andrew Torchia

DUBAI, Sept 30 (Reuters) - Saudi Arabia's economy grew at its slowest rate in more than three years between April and June, government data showed on Friday, and some analysts said the figures might be understating the extent of the blow from low oil prices.

Growth has been weakening since early 2015 as cheap oil slashes state revenues and pushes the government into spending cuts, which are weighing on the private sector and consumer spending.

Gross domestic product, adjusted for inflation, rose 1.4 percent from a year earlier in the second quarter of 2016, after growth of 1.5 percent in the first quarter. It was the slowest growth since 0.3 percent in the first quarter of 2013.

The oil sector expanded 1.6 percent from a year ago, slowing from 5.1 percent growth, while the non-oil sector grew 0.4 percent, recovering from a fall of 0.7 percent in the previous quarter. The private sector grew just 0.1 percent in the second quarter.

The figures suggested the Saudi economy was faring better in the face of oil's slump than many people feared. Nevertheless, analysts said Saudi data could be erratic - growth for the fourth quarter of 2015 was ultimately revised down to 1.8 percent from an original estimate of 3.6 percent - and said there could be a similar revision in this case.

"There's a good chance that the figures will be revised down," said Jason Tuvey, Middle East economist at London-based Capital Economics.

Other indicators such as imports suggested the non-oil private sector may have slowed further than the government data showed, he said.

Monica Malik, chief economist at Abu Dhabi Commercial Bank, said she had expected some improvement in the second quarter but that the non-oil sector's positive growth was surprising. She also said second-quarter data for the non-oil sector might eventually be revised lower.

In any case, she said, the economy would remain under pressure from austerity policies for the rest of this year. The non-oil sector looks set to contract for 2016 as a whole, she said.

This week, the cabinet announced it was cutting bonuses and other financial perks for public sector workers; since such allowances account for as much as 30 percent of many Saudis' income, the policy may have a significant impact on consumer spending and saddle banks with more non-performing consumer loans.

(Reporting by Andrew Torchia) ((andrew.torchia@thomsonreuters.com; +9715 6681 7277; Reuters Messaging: andrew.torchia.thomsonreuters.com@reuters.net))