The seizure occurred in a vegetable store in the Tripoli neighborhood of Bab al-Tabbaneh following a tip-off on Thursday night, the army said cited by Daily Star Lebanon newspaper.
The Lebanese army patrol discovered a variety of military equipment as well as 25 kilograms (55 pounds) of explosive material, 50 bombs and four rocket launchers including ammunition.
According to the Friday Lebanese Army statement, an investigation has been launched over Thursday night's incident.
In January, a double suicide attack occurred in a crowded coffee shop in Tripoli's Jabal Mohsen district, killing nine and injuring 35 people.
Northern Lebanon has seen an upsurge in violence in recent months as the ongoing civil war in neighboring Syria spills over into its territory.