Yes.
Your contributions are not locked in and can be withdrawn at least once in a 12 month period. If withdrawn, the amounts are subject to provincial and federal income tax. Fees may also apply.
Employer contributions are locked in, meaning they are protected and cannot be withdrawn before you turn 55. If your employment ends, the administrator will offer to transfer the amounts in your name to another savings instrument (an LIRA or LIF, for example). You can also choose to keep all amounts in the VRSP.