Semen is typically white-grayish in color but it may appear yellow at times since urine passes through the same tube (urethra) that semen passes through. Brown colored semen suggests old blood which can be a sign of irritation and/or infection. Any time there is a change in the color of your semen that lasts more than a couple of days, you should make an appointment with your health care provider (HCP). Be sure to tell your HCP if you are sexually active as some sexually transmitted infections (STIs) can cause changes in semen.​​