Loyalty program is common practice in service industry. Started in airlines industry, nowadays almost every service industry have loyalty programs. The objective of loyalty programs is for customer retention and futhermore will become loyal to the firm. Gamification or game-like activity is a feature that expected to build more engagement for customer and firm relationhip. This research wil study about factor-factor that influence customer for utilize gamification. Then how gamification will affect to customer engagement. Quantitative method will be used to conduct the research. sample for data collection will use customer of Tokopedia, one of the biggest marketplace in Indonesia. SEM method using LISREL will conduct the statistical analysis.