In 2009, Sitaram joined Praja Rajyam Party after resigning from TDP.
He lost the election contesting with PRP.
2012
Later after dissolution of PRP, he re-joined TDP in 2012, but was unable to adjust in the party.
2013
He joined YSR Congress Party in 2013 and contested as an MLA from Amudalavalasa constituency in 2014, but was defeated by TDP candidate K Ravi Kumar.
Sitaram belongs to Kalinga community, which has a dominant vote strength in the Srikakulam parliamentary constituency.
Sitaram is the fourth Speaker from Srikakulam district.
RLN Dora was the first speaker, Tangi Satyam was the second Speaker and K. Pratibha Bharati was the third Speaker from Srikakulam district.
2019
Thammineni Sitaram is an Indian politician from the YSR Congress Party currently serving as the speaker of the Andhra Pradesh Legislative Assembly from May 2019.
Tammineni Sitaram is a discontinued graduate in arts and is a senior leader.
His political entry started with Telugu Desam Party and was elected as MLA, 6 times (by election), from Amudalavalasa constituency.
He served as a minister for three terms, for law and justice, sports, stamps and registrations, excise and municipal administration.