Navigate to the image you want to use, select it, and then click "Insert." After the image is inserted, make sure it's selected, and then click "Picture Format." In the "Adjust" group, click "Color." Select "Set Transparent Color" near the bottom of the menu. Your cursor change, as shown below.

Select the image you want to make transparent Navigate to the Picture Format tab Open the Transparency Tool options Choose from one of the preset transparency options or click on Picture Transparency Options to choose a custom setting

1- Insert your picture and selected it. 2- Go to the Picture Format tab > Colors. 3- In the drop-down menu, select the option Set Transparent Color. 4- Now all you have to do is click on the color you want gone! PowerPoint will immediately make all that same color transparent.