Answer
Under Article 1673 of the Civil Code, the lessor may judicially eject the lessee for: (1) the expiration of the agreed or statutory period of the lease; (2) lack of payment of the stipulated rent; (3) violation of any of the conditions agreed upon; and (4) devoting the thing leased to a use not stipulated which causes its deterioration, or otherwise failing to observe the required diligence.
For residential units covered by the Rent Control Act (Republic Act No. 9653), the grounds for judicial ejectment are further regulated — for example, subleasing without the owner's written consent, rental arrears of at least three months, the owner's legitimate need to repossess the unit for his own use, or the need to make necessary repairs. Ejectment itself is pursued through a summary action — forcible entry or unlawful detainer — in the first-level court.