If i exercise a lot without changing my diet, will i still lose weight?

Yes, a small bit: About 80% of body weight is caused by the interaction of genetics and diet, 20% can be due to exercise. The vast majority of people who exercise to lose weight will simply eat a few more calories a day to make up for the calorie loss from exercise. Dropping calorie density per meal is the best way to lose weight.

Depends: In order to lose weight, you need to use less calories than you need in a day If your intake minus calories from exercise still exceeds your daily needs- you may not lose weight

Statistically, no: most studies show very little change in weight with just exercise. Several reasons: 1) stimulates eating. If you do not watch/count/lower calories, then there might be a net increase intake and even weight gain. 2) exercise increases calories out 100-600 extra per HOUR. Most people do under 2 hrs a week of 300 calorie per hour or less so... under 100 cal per day of exercise.

Possibly: But like others have mentioned, it's difficult to lose weight with exercise alone due to the compensatory response that exercise stimulates your appetite. If you really can keep your diet unchanged(particularly the caloric intake) you may be one of the lucky few, but it will take great willpower to monitor you diet and regularly exercise.