Trading Standards officers working with sniffer dogs uncovered the illicit haul at six properties in the Freeman Street area of the town.
The cigarettes and tobacco would cost an estimated Â£200,00 if bought legally.
North East Lincolnshire Council's Trading Standards team said it was the largest haul since it began a crackdown on illicit products last year.
Prior to the latest haul, the team seized nearly 90,000 cigarettes and 181lbs (82.5kg) of tobacco since launching Operation Nightshade.
Councillor Terry Walker said: "This is the most significant stash to have been uncovered during Operation Nightshade and is the result of a long-term, intelligence led campaign aimed at dishonest retailers who persist in flouting the law."

The 82-year-old, who has had health problems in recent years, reportedly does not wish to remain emperor if he has to reduce his official duties.
But a palace spokesman denied that there is any official plan for the monarch to abdicate in what would be an unprecedented move in modern Japan.
Crown Prince Naruhito, 56, is next in line to the Chrysanthemum Throne.
An unnamed government source told Japan's Kyodo news agency that the emperor, who plays a largely ceremonial role but is respected deeply by many Japanese, has been contemplating the move for about a year.
His family had accepted his decision, an unnamed palace source told NHK.
However, both palace and government sources say the Imperial Household Law would have to revised to allow for the abdication to take place.
A change to the Imperial Household Law, which stipulates the rules of succession, would require approval by Japan's parliament.
Despite a categorical denial of the reports by imperial palace spokesman Shinichiro Yamamoto, the emperor's reported wishes are being given prominent attention in the Japanese media.
Emperor Akihito has been admired for distancing the monarchy from its association with the aggressive nationalism of World War Two.
In 1989 he succeeded his father, Hirohito, who had had the status of a living god in Japan until he was stripped of that role by the victorious Americans who wrote the country's post-war constitution.
Emperor Akihito had surgery for prostate cancer in 2003 and a heart bypass operation four years ago.
In 2011, he took the highly unusual step of making a televised national address following the devastating earthquake and tsunami at Fukushima.
Five things about Japan's emperor:

The boy, Julian Hernandez, disappeared when he was five and is now 18, living with his father in Cleveland.
Bobby Hernandez, 53, was arrested and is being held at a jail in Ohio.
The FBI received a tip on 30 October that this teenager may be the long-missing child after problems he had applying for college.
The agency worked with Alabama police and the National Center for Missing and Exploited Children to confirm the boy's identity.
His mother has been notified of his recovery, AL.com reports.
His father is also charged with tampering with records in Ohio so he could obtain a driver's licence in 2012.
He is being held at the Cuyahoga County Jail in Ohio with a $250,000 (Â£164,100) bail.
Authorities suspected around the time of the boy's disappearance that his father was possibly the culprit, according to AL.com.
A missing persons database shows that Mr Hernandez said he was taking his son to pre-school in August 2002 but then fled.
About 300,000 counterfeit and illegally imported cigarettes and 330lbs (150kg) of tobacco have been seized in Grimsby.
[NEXT_CONCEPT]
Japan's Emperor Akihito has expressed his desire to abdicate in the next few years, public broadcaster NHK reports.
[NEXT_CONCEPT]
A child missing in Alabama since 2002 has been found safe in Ohio with his father, who has been charged with abduction, authorities have said.