<s>[INST] hello, when I come I have yellow semen, after it dries it has a fishy odor that can sometimes last for days even after showering. I ve been to doctors and got an STD test and they all come back negative. What can I do to fix it and what could possibly be wrong? [/INST] Thanks for asking in healthcaremagic forum  Normal semen is greyish white in colour and may vary in case of infection(Prostate). And if it is foul smelling then it may be due to infection.  So, please visit a doctor for semen analysis to rule out any abnormalities /infection.  All the best. </s>