Debutant Andy Carroll was in lively form with the Liverpool loanee adding a cutting edge to the Hammers' front line before injuring a hamstring in the second half.
Captain Kevin Nolan opened the scoring for the home side inside the opening minute and they were out of sight by the break thanks to further goals from Winston Reid and Matt Taylor.
But there was bad new for Carroll later in the day when the injury forced him to pull out of England's opening World Cup qualifiers against Moldova and Ukraine.
Carroll, who was flanked by Ricardo Vaz Te and Taylor with Matt Jarvis missing following a knock in training, was involved straight away.
A long, clearing header from James Collins was flicked on by the England international into the path of Vaz Te who played the ball in to Nolan, with Carroll's ex-Newcastle team-mate finishing firmly past Mark Schwarzer.
Fulham's debutant Kieran Richardson had the visitors' first real chance when he fired in a low effort from distance that was palmed away by West Ham goalkeeper Jussi Jaaskelainen.
With less than 10 minutes on the clock Carroll was again involved when he headed Vaz Te's cross into the on-rushing Mohamed Diame, who saw his effort tipped onto the crossbar by Schwarzer.
The Australian goalkeeper was keeping his side in the game in the opening exchanges and was called upon once more to tip Vaz Te's low shot around the post.
Nolan came close to adding a second in the 16th minute as the same combination of players who created the first goal ran riot once more.
Carroll, who had won every header he contested in the early stages, picked out Vaz Te who found Nolan on the edge of the Fulham penalty area.
This time the Hammers captain attempted a lobbed effort that landed on the top of Schwarzer's net with the home side fully in control.
Fulham started to enjoy a little bit more possession as the first half progressed but were soon further behind.
Taylor's 29th-minute corner found Reid on the edge of the six-yard area and he beat Mahamadou Diarra to the ball to power a header past Schwarzer to double the home side's lead.
Vaz Te, who was full of running and always wanted the ball, was proving a constant thorn in the side of the Fulham defence and Nolan should have done better when the Portuguese picked him out inside the box.
It was not long afterwards that the third goal was scored by the Hammers as Collins' free-kick was headed clear by Fulham's Brede Hangeland.
The loose ball broke free to the feet of Taylor who finished well from the edge of the penalty area.
Fulham had back-to-back corners in first-half injury time but could not create an opening and were almost caught on the counter-attack before the half-time whistle.
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Fulham manager Martin Jol reacted to the disastrous first half by introducing new signing Dimitar Berbatov at the interval with Mladen Petric making way.
Carroll started the second half as he did the first, winning a header that found Vaz Te, who could not direct his shot towards goal.
Taylor almost scored his second of the game five minutes after the re-start as a short free-kick was worked to him by Nolan.
The 30-year-old's effort was straight at Schwarzer but the experienced goalkeeper could not hold it and the ball was eventually cleared for a corner.
Fulham again had a spell of sustained possession but still lacked a cutting edge even with Berbatov now involved.
Carroll was replaced by Carlton Cole with just under 25 minutes remaining after injuring his hamstring in a heavy landing.
The visitors continued to press and Steve Sidwell finally forced a smart save out of Jaaskelainen following a Damien Duff corner.
Jol's side continued to show signs of improvement as Berbatov linked well with Hugo Rodallega, with the latter again testing Jaaskelainen.
West Ham boss Sam Allardyce was forced to make his third and final substitution when defender Guy Demel went down injured.
Demel was replaced by teenager Robert Hall with Taylor reverting to full-back.
Hall had the chance to put West Ham four goals ahead after Vaz Te ran the length of the field after collecting the ball from a poor Fulham corner.
The 25-year-old jinked his way into the box and rolled the ball to Hall but his shot was well blocked.
The three points had long-since been secured by the Hammers who sat back for the closing stages with Fulham chasing a consolation goal.
Berbatov certainly gave Fulham a cutting edge during the closing stages and almost created goals for Duff and Rodallega, with Jaaskelainen keeping both efforts out.