| S.N. | Male Ascaris | Female Ascaris |
| 1. | Body is about 15-30 cm long. | They are longer (20-40 cm) than males. |
| 2. | Their body is narrower. | Their body is wider. |
| 3. | The posterior end of the body is slightly tapering. | The posterior end is blunt. |
| 4. | The posterior end is curved downward or hooked. | The posterior end is straight. |
| 5. | Anus is an outlet for digestive and genital tracts, hence called cloacal aperture. | Anus is an outlet for digestive tract only. |
| 6. | Genital tract joins the rectum, forming a common chamber, the cloaca. | Genital tract doesn’t join the rectum, hence there is no cloaca. |
| 7. | There is no separate genital aperture. | There is a separate mid-ventral genital aperture of vulva at about one third of the body from the anterior end. |
| 8. | Two penial spicules or penial setae project from the cloacal aperture. | Penial spicules or penial setae are absent. |
| 9. | A cushion-like prominence occurs just in front of the cloacal aperture. | No such prominence occurs in front of anus. |
| 10. | There are pre-anal and post-anal papillae in front and behind the cloacal aperture. | There are no such papillae. |
| 11. | During copulation, the male coils itself around the female. | During copulation, the female remains straight without coiling. |
| 12. | Reproductive organ is represented by a single straight tube. | Reproductive organs are represented by two tubes present in a Y-shaped structure. |
Also see: General characteristics of phylum Aschelminthes (Nemathelminthes)