Housing Minister Margaret Burgess said she plans to change legislation currently going through Holyrood so the right-to-buy would be scrapped two years after the Bill gets Royal Assent.
The Scottish Government had previously proposed the right-to-buy - which was introduced by Margaret Thatcher - would remain in place for three years after Royal Assent.
Conservative housing spokesman Alex Johnstone claimed ending the policy was a "dark day for liberty and democracy in Scotland".
But Ms Burgess said: "This Scottish Government is committed to increasing the supply of social housing, which is why we want to end the right-to-buy.
"By doing this we will keep homes in the social rented sector, increase choice for tenants and people in need of housing and help social landlords manage their stock more effectively."
Right-to-buy, first introduced in the 1980s, gives eligible tenants the opportunity to purchase their home at a discounted price.
An estimated 534,000 tenants in Scotland currently have the right to buy their home, but the Scottish Government argues ending the policy could keep about 15,500 properties in the social rented sector over a 10-year period.
The proposal is included in the Housing (Scotland) Bill, with MSPs on a Holyrood committee already having urged the Government to speed up the abolition.
The majority of members of the Infrastructure and Capital Investment Committee called for right-to-buy to be axed within a year of the legislation gaining Royal Assent.
Today, Ms Burgess said: "I have now taken on board the committee's concerns that the proposed three-year timescale to abolish right-to-buy is too long. Going forward we will reduce the period to two years which will give tenants time to consider their options and find financial advice if they want to exercise their right to buy their home.
"These measures will protect up to 15,500 social houses from sale over a 10-year period and safeguard social housing stock for future generations.
"With 185,000 people on waiting lists for council and housing association houses, we can no longer afford to see the social sector lose out on badly needed homes."
The Housing Minister said the Government would bring forward an amendment to reduce the period from three years to two.
But Mr Johnstone hailed right-to-buy as a "transformational policy" which had "the effect of creating stable mixed tenure communities which contributed to strong, stable societies in many parts of Scotland".
The Tory said: "The opportunity taken by many to become homeowners is something which has changed lives, and will continue to change lives in the future."
Abolishing this is "a vindictive and politically-motivated move that will simply be counter-productive", he added.
"In recent years only 1,500 houses were bought by the tenants.
"Right-to-buy was withering on the vine. By moving to end right-to-buy the Government have opened a window of opportunity for hundreds of thousands of Scots who still have that right.
"The likely outcome of this legislation is that there will be a peak in demand for right-to-buy over the next two years.
"The result of that will be that many houses that would have remained in the social rented sector will now be removed as part of this process."
Labour's Mary Fee backed the abolition of the right-to-buy, but called on Ms Burgess to set out why the Government had opted for a two-year period, rather than the 12 months suggested by the Infrastructure Committee.
She also branded the Bill a "missed opportunity to tackle the housing challenges faced across Scotland".
She said: "Under the control of this Scottish Government, housing is facing its biggest crisis in Scotland since the end of the Second World War. The Bill contains no new or radical proposals to tackle the problems forced on housing by the SNP.
"Instead of proposing a bold vision to build the new houses Scotland urgently needs, we have measures that do not go far enough.
"What we have here are proposals that tinker around the edges of the serious issues that result in over 155,000 people in Scotland waiting for social housing."