The 22-year-old topped the podium in Ljubno, Slovenia, to earn her first World Cup win of 2018-19 and deny Maren Lundby a seventh successive triumph.
Takanashi, a bronze-medallist at last year's Winter Olympics in PyeongChang, also finds herself third in the overall rankings.
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The Japanese skier produced jumps of 89.5m and 82.5m as she racked up 223.9 points, edging out Norwegian series-leader Lundby (221.8).
Japan's ski jumper Sara Takanashi competes during the FIS Ladies Ski Jumping World Cup Normal Hill Individual in Ljubno, Slovenia on February 10, 2019.
Image credit: Getty Images
Germany's Juliane Seyfarth, who currently sits second, completed the podium with a score of 216.8.
The World Cup continues with two large hill events in Oberstsdorf, Germany, on February 16-17.
In the men's tour Poland's Kamil Stoch overcame Saturday speed issues to claim a second successive ski jumping World Cup victory on the large hill in Lahti, Finland.
Stoch secures back-to-back victories with superb jump in Lahti
The three-time Olympic champion struggled somewhat in Saturday night's team event, with Poland missing out on a medal in finishing fourth.
But the 31-year-old pulled round the following day, closing the gap on runaway World Cup leader Ryoyu Kobayashi in the process.
"It was a fantastic day," said Stoch.
"Yesterday I had a bit of trouble with my technique – especially on take-off, I was losing speed in the air. Today everything came back on a good level.
Stoch delighted with victory after earlier troubles
"I was happy with the second jump because I immediately knew it was a really good jump.
"The landing wasn’t perfect but everything ended for me in a good way."
Needing 121m to grab gold, Stoch flew 129m to take him to an overall total of 280.9 points, significantly ahead of Kobayashi's 263.7.
With eight events remaining the Japanese's lead at the summit of the World Cup standings isn’t unassailable – he sits on 1460 points with Stoch his nearest rival on 1029.
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