This document discusses achieving data truthfulness and privacy preservation in data markets. It proposes a system called TPDM that aims to ensure data honesty and privacy preservation simultaneously. TPDM allows data contributors to honestly submit their own data without impersonating others, and requires the service provider to honestly collect and process data. It also protects both the personally identifiable information and sensitive data of contributors. The document describes how TPDM could be implemented for profile matching and data distribution services, and evaluates its performance on real-world datasets. Ensuring both data honesty and privacy is challenging but important for the healthy development of data markets.