He was speaking at a parliamentary hearing in the wake of this summer’s terrorist attacks in Europe, including the twin attacks in Brussels that killed 32 people in March.
De Kerchove was invited to debate with the civil liberties committee any trends revealed by such attacks and EU counter-terrorism measures.
The Belgian born official told members that intelligence chiefs fear Isis may be planning to launch deadly car bomb attacks on European cities.
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Anti-terror officials, he told members, believe the jihadi terrorists could use vehicles packed full of explosives as a new ploy to bring fresh devastation to Europe.
He also warned that Europe needed to prepare for an 'exodus' of thousands of fighters returning from Iraq and Syria.
MEPs quizzed de Kerchove on his plans to cooperate with newly-appointed EU security Commissioner Julian King, and other issues such as information exchange, prevention strategies and the possibility of training Imams in Europe.
They also asked how small towns could counter the risk of an attack and EU member states’ progress in implementing the passenger name record (PNR) directive approved in April.
De Kerchove said one reason why the terrorist threat had grown in Europe is Isis' mastery of online and social media propaganda channels which expands their recruitment drive.
In his address to MEPs, de Kerchove said that the latest trends show that fewer Europeans are going to Syria, but more Europeans get “inspired” to join the jihad on home soil.
He told the meeting that terrorists are "more and more" targeting soft targets, instead of attacking symbolic buildings and institutions, and are using ready-made and easily available devices, such as knives or even trucks.
The official also praised Commission President Jean-Claude Juncker’s choice of King as security Commissioner, despite questions over the role a British government nominee could play on an EU executive as Britain prepares to leave the bloc following June’s Brexit referendum.