Mobile or SMS spam is a real and growing problem mainly due to the availability of very cheap bulk prepaid SMS packages and the fact that SMS engenders higher response rates as it is a reliable and personal service. SMS spam filtering is a relatively new task that inherits many spam filtering problems and email solutions. However, it raises its own specific challenges. This document motivates the work of SMS spam filtering and reviews recent developments in SMS spam filtering. The paper also discusses problems with data collection and availability to foster research in this area, analyzes a large corpus of SMS spam, and provides some baseline results. Spam messages have overflowed in many countries. They seriously violate personal rights, and may even harm national security. Existing filtering techniques often use traditional text sorters, which are more suitable for dealing with normal long texts, so it often faces some serious problems such as poor data and noise data in the SMS message. This research paper proposes a message theme model (MTM) for SMS spam filtering. The MTM is derived from the famous model of probability themes.