A tight stomach feeling can be caused by a variety of factors, most commonly related to digestive or hormonal issues. Common causes include indigestion, irritable bowel syndrome (IBS), constipation, food poisoning, anxiety, premenstrual syndrome (PMS), and pregnancy. Other reasons for stomach tightness may include gas buildup, overeating, or stress-related muscle tightening in the abdominal area. These sensations often arise from muscle contractions, digestive tract issues, or hormonal changes, and usually resolve with lifestyle changes or treatment of the underlying cause.