Behaviour of tiang tongkat foundation over Pontianak soft organic soil using 3D finite element analysis Peat deposits are distributed mostly along the coast of West Kalimantan Indonesia particularly in and around the provincial capital of Pontianak. There are many problems with constructing over peat soil as the existence of this type of soil always generates geotechnical engineering problems for regional development. For light construction on peat land several variations of Indonesian traditional floating wood foundations commonly called tiang tongkat foundations are still being used today. A tiang tongkat foundation of any dimension is constructed over different fields. The foundation was modelled as three dimensional linear elastic and the Pontianak soft organic soil was modelled as undrained Soft Soil Creep Model. All of the 324 models were made to be used for simulation by means of the Plaxis 3 Dimensional Foundation Program. The purpose of this analysis is to predict the load settlement behaviour and the capacity of traditional foundations. The comparison between field tests and numerical analysis and analytical solutions are also demonstrated.