In this research, we propose and study an online social network mathematical model with delay based on two innovative assumptions:
(1) Newcomers are entering the community as either potential online network users or those who are never interested in online networks at constant rates, respectively; and
(2) It takes a certain time for the active online network users to start abandoning the network.

The basic reproduction R₀, the user-free equilibrium (UFE) P₀, and the user-prevalent equilibrium (UPE) P* are identified. The analysis of local and global stability for those equilibria is carried out. For the UPE P*, using the delay τ as the Hopf bifurcation parameter, the occurrence of Hopf bifurcation is investigated. The conditions are established that guarantee the Hopf bifurcation occurs as τ crosses the critical values. Numerical simulations are provided to illustrate the theoretical results.