Prior to joining active politics, she was a lecturer at St. Anthony's College, Shillong, where she taught mass communication.

The title of her thesis was Influence of Media on Public Opinion During The Periods of Social Unrest: A Study of Meghalaya.

Lyngdoh briefly joined the United Democratic Party (UDP) in 2008 after the Indian National Congress refused to give her a ticket to contest the 2008 state Assembly elections.

[9] Lyngdoh met Indian National Congress President Sonia Gandhi in New Delhi, after which she resigned from the United Democratic Party and the Meghalaya Legislative Assembly on 31 March 2009.

[12][13] On 14 February 2022, Lyngdoh along with 4 other fellow Congress MLAs was suspended by the party for backing the BJP allied NPP state government.

Lyngdoh has served as a Cabinet Minister in the state government, and during her first two terms as a Cabinet Minister, she held portfolios including Public Works Department, Information Technology, Information & Communication, Urban Development, Housing, Labour, Education and Tourism.

[citation needed] In 2017, the High Court of Meghalaya cancelled the appointment of 365 teachers who were appointed in Government lower primary schools after allegations of irregularities in the selection process which were conducted in 2010 when Lyngdoh was the state's minister for education purportedly involved many politicians from the state.

The court also directed the Central Bureau of Investigation to probe the "criminal aspect" of the irregularities that were alleged to have marked the selection process.

In 2013 she contested the East Shillong Constituency, defeating the UDP candidate and former Deputy Chief Minister Bindo M Lanong.