She was joined on the winner's podium by Swiss snowboarder Iouri Podladtchikov, who claimed his first New Zealand Burton Open half-pipe title in his fifth appearance at the event.
Wanaka siblings Mitchell and Kendall Brown both secured top-10 placings in their respective men's and women's fields.
Kendall finished the half-pipe as the best-placed New Zealander, when she came eighth in the women's competition, while brother Mitchell came ninth.
Podladtchikov and Clark held off strong challenges from an expanded field of competitors, after organisers were once again forced to re-jig the format of the finals schedule because of weather conditions.
Overnight rain and warm temperatures necessitated the change in format on Saturday as event directors tried to preserve Cardrona's Olympic-standard half-pipe, after low cloud, swirling mist, and near-zero visibility levels had disrupted Friday's slopestyle finals.
All 38 men and 19 women semifinalists went straight into a single final round, with the best of two runs counting for their final half-pipe ranking.
Podladtchikov (21), nicknamed I-Pod by his snowboarding peers, showed good early-season form at Cardrona and his first NZ Open title win backs up a maiden Burton Open half-pipe title in Canada in February.
He was pushed hard by 14-year-old Burton Open debutante Taku Hiraoka, of Japan, who amazed spectators with the height and audacity of his aerial tricks.
Hiraoka, who proceeded to the half-pipe finals as the top qualifier, completed a run which belied his age and left other more experienced competitors, such as third-placed Louie Vito (US) in his wake.
Podladtchikov was "stoked" to have landed some difficult tricks to boost his finals score.
"It feels great to win here. I landed a 'double McTwist' and I haven't done that trick in competition since the US Open [in March]. It made my day," he said.
Clark's fourth NZ Open win in the half-pipe - she also won in 2006, 2007, and 2009 - came courtesy of a first run which earned her an 88.70 point score from the judges.
The effort saw her coast to victory over second-placed Spanish snowboarder Queralt Castellat, whose best run left her more than six points behind Clark's winning score.
The re-jigged finals did not disrupt the 2002 Winter Olympic half-pipe gold medallist.
"Any time the format changes its kind of a disadvantage.
"You strategise and ... when you go from three runs down to two [in the finals] you have to re-evaluate,"I ended up walking away with the run I wanted to do," she said.
New Zealand snowboarders did not leave the Burton Open competition empty-handed, with Whangamata rider Ben Stewart claiming the men's best half-pipe trick in a rejuvenated competition brought back for this year's event.
Stewart (18) is among New Zealand's best up-and-coming riders and will lead a young Kiwi team at the FIS Junior Ski and Snowboard World Championships next week.
He finished 34th in the half-pipe, after initially missing out on the finals by two places during Thursday's qualifications, but was called up on Saturday to replace other competitors.
