Which is better job??working in software development or software testing? and why?

I think it depends on what kind of software development and what kind of testing. For instance, a QA analyst might make more than an html developer. Also, there is usability/accessibility testing. These kinds of testing for major companies pay quite a lot more than their developer counterparts (In the companies I've worked for anyway).

That said, you will need to learn more for software development. If you are a tester, you will need to learn testing principles and test software and think of input/conditions that could break that software. But for software development, typically you will need to know a few technologies/programming languages, how to use them, benefits of each, best practices, methodologies, etc. along with at least basic knowledge of the testing principles

What counts in both fields is experience. So the longer you've been working in one type of field, the more you will earn. The comparison between "software quality assurance" and "Intermediate Level Software engineer" (I think it is the best comparison as they both require about the same years of experience and you are testing what engineers are developing) found that the engineer earned about 5 grand more (69k/year) to the tester (63k/year). This comparison was made on salary.com for my location in the U.S. It may show vastly different results for your area.

http://www.salary.com

I agree with others that ultimately, it shouldn't be what salary you earn, but what you like to do. Software developing can be frustrating because your code won't work for some stupid bug and the testers are always coming back with things that are wrong. You are more the go to person with this kind of job for a problem. Testing, well, just a different job. (you may be asked to field test, come with input for software to crash it, etc.)

Clearly, software development would be much harder than testing, but if you enjoy one over the other, take the one you enjoy Development should pay more and have you working harder, testing your knowledge, and tessting should just test your "using the software" skills.

Really it depends on your interest, ergo nowadays we've a new engineering which is called software quality engineering it means that you are talking about two majors.