In this thesis, after a survey on shape memory, exchange bais and magnatocaloric effect, W doping on structural, magnetic, electrical and magnetocaloric properties of Ni-Mn-Sn ferromagnetic shape memory alliys are studied. The samples was prepared by mechanical allying. High purity of elements (all with purity 99.5%) were ball-milled under an argon atmosphere. The ball-to-powder weight ratio was 10:1 and ball-milling was carried out over several cycles of 1 h and 5 min rest stages up to 30 h. Then, samples were compacted and encapsulated in quartz tubes under high vacuum and heat treated at 1223 K for 16 h, the samples were got rapidly quenching in cold water. Phase identification was carried out using an X-ray diffraction system (XRD) with Cu K? radiation at room temperature. The XRD pattern of the samples indicate that the Ni 47 Mn 40 Sn 13 is single phase and it has L2 1 structure. But with creating and increasing of the amount of W substitiution in Ni, Mn and Sn site, samples will go out of single phase. Thermals behavior were determined from differential scanning calorimetric during heating and cooling to investigate the martensite phase transition. Magnetic susceptibility of all the samples indicates a magnetic transition in the vicinity of astenite Curie temperature and martansite transition (MT) in the vicinity of MT temperature. Also the dynamic critical exponent model confirmed the cluster spin glass behavior below the MT temperature. The magnetization measurement was conducted using a SQUID magnetometer up to 5 T. The splitting of the ZFC and FC M(T) curves can be explained by the coexistence of ferromagnetic and antiferromagnetic interactions in the W0, W1Ni and W1Sn samples. Since below Neel tempreture the EB effect appears, this transition is named as the conventional exchange bias temperature, (T EB ). In addition magnetocaloric effect (MCE) of samples were investigated by M(T) measurements. Direct measurements of the adiabatic temperature change (?T ad ) have been done using home-built instrument under the magnetic field of 1.96 T. The correct estimation of inverse MCE in materials experiencing MT is important for development of magnetocaloric refrigerators to be used in magnetic-cooling technology. In this work, we compare direct and indirect measurements of value samples in the vicinity of MT. Calculated and observed ?T ad values are found to be in a good agreement. In the direct measurements, the maximum absolute values of the magnetic field induced temperature change of ?T ad =2.2 K at 1.96 T was obtained for W1Ni sample. This value of ?T ad is in the range of the highest ones observed in Ni-Mn-Sn Heusler alloys below 2T. Correct estimation of the inverse MCE in materials experiencing an uninterrupted MT is demonstrated in the present work which is important for the further progress in magnetocaloric cooling. In the end, there is a summary of thesis and suggestions for further studies.