Record of highest individual score by a batsman in India v New Zealand test match belongs to Graham Dowling, the right handed opener who played 39 tests for Kiwi team and made 2306 runs.
It was the second test match on 1968 India's tour of New Zealand and home team were 0-1 down after Indians won first test at Dunedin by 5 wkts. In this test match, from begining thanks to Dowling's double century, home team dominated and won the game by 6 wkts. Dowling, in first innings, made 126 run opening partnership with Bruce Murray and then added another century stand with Mark Burgess. Dowling was out stumped, trying to accelerate innings.
Dowling made 5 runs in second innings as Kiwis lost 4 wkts in chasing down 88.
Highest score by an Indian batsman in a test match against New Zealand is 231 by Vinoo Mankand, another right handed opener who played 44 tests for India and made 2109 runs. in this 5th test match on New Zealand's first ever tour of India back in 1956, Vinoo Mankad added 413 runs for the first wicket with Pankaj Roy which is still the highest opening stand by any Indian pair ever.
Mankand's innings at Corporation ground in Madras (now Chennai) allowed India to declare at 537 for 3 wkts and they won the match by an innings and 109 runs.
Highest score by a New Zealand batsman in India is unbeaten 230 by Brett Sutcliffe at Feroz Shah Kotla while best by an Indian player in New Zealand is 192 by Mohammad Azharuddin off just 259 balls at Auckland back in year 1990.
What are the other biggest scores by batsmen in Ind v NZ test matches over the years? following list is limited to scores over 170.