Competitive analysis plan section of a business plan talks about the competition that a business faces. When you do a market research, part of it is to analyze the competition along with its strengths and weaknesses.
Talk about any advantage that you have over your competition in terms of your own product or service as well as any strategy that you are going to implement to supersede or thwart the competition.
The competitive analysis is very important because you do not want to make the mistake of assuming that there is no competition for your product. Even when there is no direct competition there mostly is in-direct competition with other businesses in the same field or industry.
Recognizing this early in your plan and having a strategy to deal with it helps you avoid rude shocks when you do not do business. Failing to analyze your competition can make the rest of your business plans become completely useless. In fact a lot of your plans such as marketing strategy and pricing of the product or service will depend upon what the competition is doing.