How important is to include an acknowledgment in the poster presentation? The organization where I work provided me funding for a poster presentation. My opinion is to acknowledge the funding organization due to the research team of an organization is the authors of the paper. 


  How important is to acknowledge the funding agency?


I am using Logo of organization in the poster.  


  Using the Only logo will be good without acknowledgement in the
  poster in Acknowledgement heading?
It is acceptable to use one or both ways unless there is a restriction policy from your organization or the committee of the event, at which the poster is going to be presented. 

However, a poster is very short to present your work and ideas and you want to properly invest in the space. In my opinion, a logo is enough to acknowledge the funding agency. The assumption is that there are no other reasons to put a logo of any organization in your poster if it does not support the work in one way or another.