The 2nd New Zealand Parliament was a term of the Parliament of New Zealand. It opened on 15 April 1856, following New Zealand's 1855 election. It was dissolved on 5 November 1860 in preparation for 1860 election . The 2nd Parliament was the first under which New Zealand had "responsible government", meaning that unlike in previously, Cabinet was chosen (although not officially appointed) by Parliament rather than by the Governor.

Political parties had not been established by the time of the 2nd Parliament, meaning that anyone attempting to form an administration had to win support directly from individual MPs. This made forming a government difficult. The first administration, led by Henry Sewell, lasted only two weeks, as did the second, led by William Fox. The third ministry, led by Edward Stafford, was more stable, governing for the remainder of the 2nd Parliament and for the beginning of the 3rd.

The 2nd Parliament, which used the same electoral boundaries as the 1st Parliament, consisted of thirty-seven representatives representing twenty-four electorates. Two regions of the country (the inland regions of the lower North Island and the northwest corner of the South Island) were not part of any electorate, and so were not represented.

Electoral boundaries for the 2nd Parliament

Initial composition of the 2nd Parliament

Changes during term

The turnover of MPs was very high in the 2nd Parliament, with at least twenty by-elections being held. This situation was partly the result of a redistribution of electoral boundaries agreed upon in 1858, which total number of seats in Parliament rose from thirty-seven to fifty-three. Most of these seats added to already-existing electorates, but several new electorates were also formed. The northern portion of the Northern Division electorate became the electorate of Marsden, while the Wairarapa and Hawkes Bay electorate was split into its two separate components (with Hawkes Bay also expanding inland into unincorporated areas). The southern portion of Wairau electorate, plus part of Christchurch Country, became the new Cheviot electorate, and the western portion of Dunedin Country became the new Wallace electorate. In addition, the Wanganui and Rangitikei electorate expanded inland into unincorporated areas, leaving the northwest of the South Island as the country's only territory not part of an electorate.