Yes, website theme can affect keyword ranking. A website theme that is well-coded, fast, and mobile-responsive can positively impact the website's keyword ranking. This is because search engines prioritize websites that provide a good user experience and are easy to navigate. On the other hand, a poorly coded or slow website theme can negatively impact keyword ranking as it may lead to a high bounce rate and lower user engagement. Additionally, a website theme that is not optimized for SEO may also negatively impact keyword ranking. It is important to choose a website theme that is SEO-friendly, fast, and provides a good user experience.