The snout otter clam Lutraria rhynchaena - “Tu hai” is one of the seafood sources with very high nutritional and commercial values in Viet Nam. Currently, it is being cultured commercially in the northern and the central provinces. For the limited availability of seed, however, it could have met the demand for consumption in the markets. This research was performed to trials and optimized method of spawning induction so as to record seed artificial reproduction. The broodstocks were stimulated to reproduce in some different methods such as high thermal shock by weak sunlight exposure, low thermal shock, and high pH shock in natural seawater. The results showed that pH shock at 9.5 for 20 minutes and the low thermal shock at 15oC for 20 minutes were suitable for spawning. Both of the above methods yielded 100% of the broodstocks to reproduce, the reproductive indexes were high and the ratio of unfully developed veliger larvae stage was low. These results suggested that these two methods of stimulation could be processes of the artificial production of “Tu hai” for commercial scale.