After 10 minutes, Jamaal Lascelles scored from Matt Ritchie's corner, but the Knights held the lead for 75 seconds.
Eddie Howe was absent for his first game in charge of Bournemouth as they were held to a 2-2 draw by Wolves.
The new head coach was forced to watch the game from his hotel room after testing positive for coronaviruses on Friday, with his assistant directing the team from the sidelines.
As he settles into his new role, he will have seen a game to offer encouragement and also illustrate the size of his task to keep the club in the top flight.
The home fans signed Howe's name from the first minute, and that led to the early goal by Jamaal Lascelles.
Ivan Toney took advantage of Karl Darlow's mistake to fire in low against his former employers and celebrate in front of the Gallowgate End.
After several loan spells, the 25-year-old, who was sold by Newcastle to Peterborough in 2018, was twice close to scoring again, being caught slightly in the air and having a goalbound shot cleared off the line.
Rico Henry stabbed a shot past Darlow to give Thomas Frank's team the lead after 31 minutes.
After Allan Saint-Maximin's cross, Joelinton curled into the bottom corner for his first goal of the season.
Saint-Maximin salvaged a point when he crashed in at the back post following a flowing move, after the Bees went ahead once more when substitute Frank Onyeka's shot was diverted past Darlow via Lascelles.
Despite being held to a goalless draw, Newcastle continued their worst start to a league campaign, falling to 20th, while Thomas Frank's Brentford ended their four-game losing streak.
There are signs of Howe influence.
After Howe's appointment 12 days ago, things seemed to have settled down over the international break, with the new head coach using the time to influence the squad with his methods.
He was going to watch his first game from his hotel room and send messages to his staff via the phone after a positive coronaviruses test.
It was unique, but perhaps fitting for a club where entertainment and gallows humor is always in demand.
Howe will see that the season has left them mired in the bottom three because of their poor defence.
He promised to offer the type of football that would "do the fans and city proud", and as Saint-Maximin was dazzling up front, Jonjo Shelvey sprayed passes to both wings and Joe Willock provided in the middle, the supporters were happy.
There appeared to be an increase in intensity to the play of the hosts.
It showed that there is more to be done to make the club a more solid outfit as Toney and Bryan Mbeumo cut through the hosts' defence.
Toney was a menace at times, testing a back three of Lascelles, Clark and Schar in the 3-4-3 set-up, and he could have had a hat-trick.
In the second half, the situation changed as the team tried to tighten up.
They went behind to Lascelles' own goal and Tindall or Howe made a double substitution, which changed the formation and proved crucial.
Sean Longstaff replaced Willock in the middle, and Ryan Fraser came on and provided a delightful cross from the best move of the game.
With the crowd in raptures, there was still time to get a winner, but after another quick break, and the goal at his mercy, he slipped to massive groans all around St James' Park.
The team is still five points from safety despite the Howe revolution and there are many issues still to be resolved.
There is a city calledNewcastle United.
Brentford
Line-ups.
Match statistics.
Live text.
Formation 3-4-3.
Shelvey11Ritchie is the 23Murphy28 Willock8
7Joelinton9Wilson10Saint-Maximin
26Darlow
Substituted for Longstaff at 71' minutes.
6 Lascelles.
2Clark.
23Murphy.
Willock replacedFraser at 71 minutes.
Shelvey is 8.
11Ritchie.
7Joelinton
Wilson was booked at 46 minutes.
The book was written at 75 minutes.
Substitutes.
1Dbravka.
12Lewis.
Hayden is 14.
17Krafth
Manquillo
21Fraser.
24Almirn
Gayle was 34.
36S Longstaff.
Formation 3-4-3.
Roerslev18Jansson5Pinnock
7Cans 27Janelt6Nrgaard3
40Fernndez
Substituted for Goodeatminutes.
18Jansson
5Pinnock
7Cans.
Substituted forBaptiste at 89 minutes.
The book was written at 83 minutes.
3Henry.
19Mbeumo
17 Toney
Substituted for Onyekaat at 59' minutes.
Substitutes.
2Thompson
Goode
9Forss
15Onyeka.
The person is 26Baptiste.
28Bidstrup
33Maghoma
Haygarth
41 Cox.
The match ends with a 3.
The second half ended with a 3.
A corner, of course. Pontus Jansson Conceded.
Jonjo Shelvey won a free kick in the defensive half.
Rico Henry had a foul.
An attempt was missed. Wilson's shot from the right side of the box is close, but misses to the right. They assisted by Joelinton.
The hand ball was by the person.
There was a substitution for Brentford. The new person is Shandon Baptiste.
An attempt was missed. Wilson's headed shot from the centre of the box misses to the left. Ryan Fraser assisted with a cross.
The attempt was blocked. Allan Saint-Maximin's shot from outside the box is blocked. Jonjo Shelvey assisted.
Christian Nrgaard was shown a yellow card for a bad foul.
There was a substitution for Brentford. Mads Roerslev was replaced by Charlie Goode.
An attempt was missed. Bryan Mbeumo's shot from outside the box is too high. Ivan Toney assisted with a headed pass.
The corner is at Brentford. Karl Darlow was in the match.
Allan Saint-Maximin was shown a yellow card for excessive celebration.
Goal! There were three games, including a 3 by Newcastle United. Allan Saint-Maximin shot from the centre of the box to the bottom left corner. Ryan Fraser assisted with a cross.
Ciaran Clark was the culprit.
Bryan Mbeumo won a free kick.
There is a substitution for the United States. Sean Longstaff is the new person.
There is a substitution for the United States. Ryan Fraser is in charge of Joseph Willock.
