The quick answer is no. Age will not hurt your application - if you're truly prepared. It’s never too late to learn new things and carve out a new career path. But it may be more difficult to get into graduate school after a having career as compared with applying straight out of college simply because of the gap in your education. That said, much depends on your career and the discipline you wish to study. Some fields, like business, usually prefer applicants to have some experience. Science fields emphasize a background in science and math. Recent coursework in these areas will aid your application.
First, consider the graduate program's requirements. Are there any expectations about a particular major, coursework, or outside experiences? Evaluate your background and skill set. Do you have the basics? If not, what can you do to enhance your application. You might take classes in statistics, for example, or volunteer to work in a faculty member's lab.
Second, consider your application. Given the gap between completing college and applying to grad school, GRE scores may be even more important for your application because they indicate your potential for graduate study. In the absence of recent indicators (such as graduating within the last few years), standardized test scores may be scrutinized more closely. When it comes to recommendation letters, there are a variety of options, but try to get at one that evaluates you within an academic context. Also get a letter(s) from recent employers as they have a current perspective of your work habits and skills.
Third, know what you're getting into. Graduate study is not glamorous and not always interesting. It is hard work . You'll be broke. A research assistantship, teaching assistantship, and other funding resources can pay for your tuition and sometimes offer a small stipend but you're not going to support a family on it. If you have a family, think about how you'll manage your family responsibilities. Where will you study and how will you carve out uninterrupted time? You will have more work than you can imagine and it will require more time than you plan. Think about it now so that you're prepared later - and so you prepare your family to support you as needed. There are many students who combine grad school and family quire successfully.
