A high standard deviation indicates a lot of variation in the values within the group. It is neither good or bad. It depends on the kind of observations you are making and the methods you are using to make these observations.

I suggest you examine a distribution of the data to see if there are any unusual values, such as data entry errors, that may have affected your std. dev.

In general, a high standard deviation means that the estimate you are getting from your data may be far from the answer you would get with complete data. Often the reason for high standard deviations is that you have a small sample size, or are producing estimates from a small subset of your sample. Sometimes it means there are substantial variations within the data, including from outliers that are very different from most observations, or from substantial variation in general. High standard deviations are undesirable in the sense that you cannot attach much confidence to generalizing from your data.