The Gunners beat the east London outfit 5-2 on Saturday evening - with each of the goals being scored before the break in what proved to be a nervy ending for the visitors.
Mikel Arteta's men looked to be on course for a huge victory after racing into a 4-0 lead after just 36 minutes.
Goals from Gabriel, Leandro Trossard, Martin Odegaard and Kai Havertz saw thousands of Hammers fans heading for the exit at the London Stadium.
But a quickfire double from Aaron Wan-Bissaka and Emerson Palmieri silenced the visiting Gooners, who feared a shock comeback could be on the cards.
Arsenal fans would have thinking of their 4-4 draw away at Newcastle in February 2011 where they became the first Premier League team to throw away a four-goal lead.
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However, away supporters were soon cheering again when Bukayo Saka restored Arsenal's three-goal lead in the fifth minute of first half added time.
The seven goals scored mean Arsenal vs West Ham has become the fourth fixture to have seen seven strikes in the opening period.
Blackburn's clash with Leeds in September 1997 was the first match to see seven goals scored, with no goals after the break in a 4-3 win for the Whites.
Bradford vs Derby then levelled the tally in April 2000, with that match ending 4-4.
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The last game to see even goals scored in the first half was Reading's thriller with Manchester United in December 2012 - that also had no second half goals and finished 4-3 to the Red Devils.
And eerily, Arsenal and West Ham have added to that after failing to find the back of the net in the second half.
The goalscoring Premier League record wasn't the only impressive feat from the first half.
Arsenal have become the first team in Premier League history to score 60 away goals against a single opponent.
They have also become the first team since Manchester City in 1937 to score at least five away goals in a single calendar year.
History was also made after Odegaard and Saka both scored from the penalty spot for Arsenal.
Arsenal have now had two different penalty goalscorers in the first half of a Premier League match for the first time.
Meanwhile Saka has become the first player in the top-flight this season to chip in with ten assists after providing two for his teammates in the first half.
And with his goal, he has joined Mohamed Salah in being the second player to boast at least 15 goal involvements in the league so far.
The England international and Salah are also now the only two players in the division to both score and assist in four different league matches this term.
Arsenal's victory over West ham has lifted them into second spot - six points behind leaders Liverpool.
Attention for the Gunners now turns towards Wednesday night's clash with rivals Manchester United at the Emirates.
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As for West Ham, they remain in 14th spot, with Julen Lopetgui's men now losing six of their 13 league matches.
They have also now lost three home London derbies in a row for the first time since 2008.