A ramp apparatus for a curtain airbag for a vehicle, positioned between a headliner and a vehicular body panel such that the curtain airbag is deployed through a matching part formed between the headliner and a pillar trim, may include a support ramp fastened to the vehicular body panel and receiving a lower portion of the folded curtain airbag, and a deployment ramp extending from a first end of the support ramp to enclose a portion of the curtain airbag therein and deploying towards the interior of the vehicle to seal a gap between the vehicular body panel and the pillar trim by expansive pressure of the curtain airbag in the event of a vehicle collision.