Voting began at 8 a.m. in 23,318 polling stations in 95 of the state assembly's 182 constituencies. An electorate of 19.8 million is expected to exercise their franchise.
As many as 10,126 stations have been declared 'critical'.
Of an estimated 19.8 million voters, 10.3 million are male and 9.5 million female.
There are a total of 820 candidates in the fray, including 49 women.
The Bharatiya Janata Party is contesting all 95 seats, the Congress 92 and the Gujarat Parivartan Party (GPP) of former BJP chief minister Keshubhai Patel 84.
Also in the fray are 84 candidates of the Bahujan Samaj Party (BSP) and 284 Independents.
Among the key constituencies that will see polling Monday are Ellisbridge, where slain BJP leader Haren Pandya's widow Jagruti is contesting against the BJP, and Naranpura, where Modi's confidant Amit Shah, a former minister, is a candidate.
The first phase of polling Dec 13 saw a 68 percent turnout.
Counting will be held Dec 20.
