We need much more information in order for us to help you.
What version of Premiere Elements and on what computer operating system is it running?
What are the properties of this video that is presenting in Premiere Elements project workspace with no video, but just audio?
Do you know the brand/model/settings for the camera that recorded that video? Posting that information may provide part of the information to help us target the issue.
Also important, do you have QuickTime (latest version) installed on your computer with your version of Premiere Elements?
Also, is your video card/graphics card driver version up to date according to the web site of the manufacturer of the card?
And, if you have Premiere Elements 10, does your computer use a NVIDIA GeForce video card/graphics card?
Please review and consider and supply more information as indicated.
Any questions or need clarification, please do not hesitate to ask.