The visitors, who were thumped 6-1 in the same fixture last season, have yet to win a game in the new campaign but came out with an ambitious attacking lineup.
They were quickly on the back foot as Zlatan Ibrahimovic, Lionel Messi, Daniel Alves and Seydou Keita put Barca 4-1 up halftime.
Atletico's Sergio Aguero pulled one back just before the break and Diego Forlan bagged another goal near the end, before Messi cracked home his second of the night.
"We were 2-0 down before we even got going," Atletico coach Abel Resino said.
"I am annoyed that their first five attacks produced four goals for them. At least we attacked more in the second half. We haven't got time to spend too much time worrying over this game."
Barca maintained their 100 percent record to stay top with nine points ahead of Real Mallorca on seven, after the islanders cruised to a 4-0 victory over Tenerife earlier on Saturday.
Real Madrid, on six points, host Xerez on Sunday.
Sevilla won 2-0 at Osasuna with goals from Alvaro Negredo and Frederic Kanoute, while Espanyol dragged themselves off the foot of the table with 3-2 win at Deportivo Coruna.
Racing Santander earned their first league win of the season by overcoming Malaga 2-1 away.
EARLY INTENT
Barca signalled their intent early on at the Nou Camp when Thierry Henry rattled Atletico's crossbar after only a minute.
It only took them another minute to open the scoring, when Ibrahimovic burst through on to a Sergio Busquets pass to flick the ball past Atletico's second choice keeper Roberto.
Messi made it 2-0 after 16 minutes running on to Xavi's pass over the top, and Alves drilled an impressive freekick past Roberto from all of 30 metres out on the half hour.
With halftime approaching Ibrahimovic conjured a pass to Messi who juggled the ball, cut past his marker and crossed for Keita to sidefoot home the fourth past a statuesque Atletico backline.
Atletico kept battling away and Aguero managed to pull one back on a breakaway, lifting the ball over Victor Valdes.
The visitors continued to press and Forlan lashed in a second, before Messi slotted home another scything passing move at the end.
Adriano Correia set up Sevilla's opener after 37 minutes when he spun clear of his marker and crossed for Negredo to score from close range.
Mali striker Kanoute scored from outside the area, shortly after coming on as a substitute, in the 71st minute and Osasuna's threat faded with a late red card for Sergio Fernandez.
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